Money & business
Personal Finance, Loans & Credit
- Mortgage Payment CalculatorAmortised loan formulaThis calculator gives you the number that actually leaves your bank account each month — not just principal and interest, but…
- Auto Loan Payment CalculatorAmortised loan formula; Regulation Z finance-charge disclosureThe payment a dealer quotes is built from more than the sticker price. Sales tax, documentation and registration fees, and any…
- Student Loan Payment Calculator34 CFR §685.208 Direct Loan repayment plansFederal student loans default to the standard ten-year plan, but three structures are available to most borrowers and they…
- Credit Card Payoff CalculatorRevolving credit, average daily balance methodA credit card has no term. Unlike a mortgage or a car loan, nothing in the agreement says when the balance reaches zero — that…
- Savings Goal CalculatorFuture value of an ordinary annuityEnter what you are saving for, what you have, what you can put away each month and the account's APY, and this calculator…
Investing & Retirement
- Compound Interest CalculatorRegulation DD (12 CFR 1030) APY conventionThis calculator projects what a starting balance plus a regular deposit becomes after any number of years, at any compounding…
- SIP (Systematic Investment Plan) CalculatorFuture value of an annuity dueA systematic investment plan is a standing instruction to buy units of a mutual fund with the same amount every month. This…
- 401(k) Growth CalculatorIRC §402(g) & §415(c) contribution limitsThis calculator projects what your 401(k) will be worth on the day you retire. It compounds your existing balance monthly, adds…
- Safe Withdrawal Rate CalculatorBengen (1994) and Trinity study frameworkThe 4% rule sets your first year's withdrawal at 4% of the portfolio and then raises that dollar amount with inflation every…
- FIRE Number Calculator4% rule (Bengen 1994) / Trinity studyYour FIRE number is the portfolio value at which withdrawals cover your spending, so paid work becomes optional. It is one…
Real Estate & Property Investment
- Cap Rate CalculatorIRV income capitalisation (Appraisal Institute)The capitalization rate is the unleveraged annual yield a property throws off: net operating income divided by price. This…
- Investment Property Mortgage CalculatorAmortised loan formula; Fannie Mae investment-property LLPAsA loan on a rental costs more than the identical loan on a home you live in. Agencies price non-owner-occupied risk through…
- Price Per Square Foot CalculatorANSI Z765-2021 (single-family square footage measurement)Price per square foot is a sale price divided by the property's gross living area. It is the fastest way to compare houses of…
- Fix and Flip Profit CalculatorStandard flip pro forma (ARV less all-in cost)This calculator runs a complete flip pro forma from after-repair value down to the number that lands in your account: net…
- Prorated Rent CalculatorLease proration conventions (30-day, actual-days, annualized)When a tenant moves in or out part-way through a month, the rent for that month has to be split. This calculator does it three…
Tax, Payroll & Insurance
- Progressive Tax Bracket CalculatorIRC §1 graduated rate schedule (Rev. Proc. 2025-32)Enter your taxable income and this calculator walks it up the federal graduated rate schedule one bracket at a time, showing…
- Quarterly Estimated Tax CalculatorIRC §6654 estimated tax; Form 1040-ESIncome without withholding has to be paid for as you earn it, in four instalments, or the IRS charges interest on the…
- Rental Property Depreciation CalculatorMACRS GDS: 27.5-year residential / 39-year nonresidential, mid-month conventionDepreciation is the largest deduction most rental owners take and the one most often computed wrongly, because three things…
- Sales Tax CalculatorState and local sales and use tax; sourcing under Wayfair (2018)Sales tax in the United States is almost never one rate. A single purchase can carry a state rate, a county rate, a city rate…
- Gross to Net Paycheck CalculatorIRS Publication 15 and 15-T (2025)This calculator walks a gross paycheck all the way down to the amount that lands in your account, in the order payroll actually…
Insurance & Risk Management
- Auto Liability Coverage Limit CalculatorCCPA Title III garnishment cap (15 U.S.C. §1673)Liability limits are not sized against the car you drive. They are sized against what a plaintiff could collect from you if a…
- Dwelling Coverage A Replacement Cost CalculatorISO HO-3 coverage structure and loss settlement conditionCoverage A is the limit that rebuilds your house, and it has almost nothing to do with what the house would sell for. Market…
- Life Insurance Needs Analysis CalculatorFamily needs (capital needs) approachThe needs approach asks what your family would actually have to fund if your income stopped tomorrow, then subtracts what they…
- Health Plan Total Annual Cost CalculatorACA cost-sharing structure: deductible, coinsurance, out-of-pocket maximumThe cheapest health plan is never the one with the lowest premium, and it is never the one with the lowest deductible either…
- Disability Elimination Period CalculatorChoosing a longer elimination period on a disability policy is the cheapest premium reduction on the quote sheet, and it is the…
Corporate Finance & Valuation
- Net Present Value (NPV) CalculatorDCF · NPV decision ruleNet present value tells you what a project is worth today, in cash, after paying for the money it ties up. Enter the up-front…
- WACC CalculatorWeighted average cost of capital (market-value weights)WACC is the blended return a company must earn on its whole asset base to satisfy every provider of capital at once. This…
- DCF Enterprise Value CalculatorUnlevered DCF (FCFF discounted at WACC)This calculator runs a full unlevered discounted cash flow model. You give it a base free cash flow to the firm, a growth rate…
- Enterprise Value CalculatorEnterprise value bridge conventionEnterprise value is what it would cost to buy the whole operating business: the market value of the equity, plus every other…
- Earnings Per Share (EPS) CalculatorASC 260 / IAS 33This calculator gives you basic earnings per share the way the accounting standards define it: net income less preferred…
Accounting & Financial Statement Analysis
- Current Ratio CalculatorASC 210-10 / IAS 1 current classificationEnter the two subtotals from the top of your balance sheet and this calculator returns the current ratio, net working capital…
- Accounts Receivable Turnover CalculatorUS GAAP statements (ASC 310) · 365-day yearReceivables turnover tells you how many times a year you sell on credit, collect the cash, and lend it out again. Enter net…
- Interest Coverage Ratio CalculatorUS GAAP / IFRS income-statement definitionsInterest coverage says how many times over your operating profit could pay this year’s interest bill. This calculator returns…
- Gross Profit Margin CalculatorUS GAAP income statement (ASC 606, ASC 330)Enter net revenue and cost of goods sold and this calculator returns gross profit in dollars, gross margin as a percentage of…
- Contribution Margin CalculatorContribution-format (variable) costingContribution margin is what one sale leaves behind after the costs that exist only because the sale happened. Enter your…
All 41 accounting & financial statement analysis calculators →
Business, Marketing & E-commerce
- Markup vs Margin CalculatorRetail pricing arithmetic (markup on cost vs margin on price)Markup and margin describe the same dollars of gross profit, but they divide it by different numbers — markup divides by cost…
- ROAS Calculator (Return on Ad Spend)MASB Common Language Marketing DictionaryROAS is attributed revenue divided by ad spend, and on its own it tells you almost nothing about whether a campaign made money…
- Conversion Rate CalculatorEnter visitors and conversions and you get the rate, the number of visitors it currently takes to buy one conversion, the…
- Customer Acquisition Cost (CAC) CalculatorMASB Common Language Marketing DictionaryCustomer acquisition cost is what one new customer costs you to win. This calculator gives you the two figures that actually…
- MRR CalculatorNon-GAAP operating metricMonthly recurring revenue is the normalised monthly value of every subscription you have contracted right now. This calculator…
Legal, Claims & Settlements
- Personal Injury Settlement CalculatorRestatement (Second) of Torts §924This calculator builds a personal injury claim the way a demand letter does: documented economic losses first, then a…
- Unpaid Overtime Back Pay CalculatorFair Labor Standards Act, 29 U.S.C. §207Unpaid overtime is calculated from the regular rate , not from the hourly rate on your offer letter. The regular rate includes…
- Child Support Estimate Calculator45 CFR 302.56 state guidelines; Wisconsin DCF 150 percentage standardThis calculator runs the two guideline models that between them cover almost every U.S. state: income shares , which prorates a…
- Probate Fees & Executor Compensation CalculatorCalifornia Probate Code sections 10800 and 10810 statutory scheduleIn a statutory-fee state, probate compensation is a formula rather than a bill: a tiered percentage of the gross probate…
- Judgment Interest CalculatorState statutory judgment interest; 28 U.S.C. 1961 for federal judgmentsA money judgment earns interest from the day it is entered until the day it is paid, at a rate set by statute rather than by…
Math & science
Arithmetic, Algebra & Number Theory
- Percentage CalculatorBase-100 proportion identityEvery percentage question is one of three questions, and this calculator answers all three at once. Enter a percent and a whole…
- Proportion Solver CalculatorCross-multiplication property of equal ratiosA proportion says two ratios are equal: a/b = c/d . Give this calculator any three of the four terms, say which one is missing…
- Adding & Subtracting Fractions CalculatorEnter two fractions or mixed numbers and this calculator adds or subtracts them exactly — no rounding, no decimal drift. It…
- Exponent CalculatorLaws of exponentsAn exponent is repeated multiplication, and everything else about exponents follows from keeping that idea consistent. This…
- Quadratic Equation CalculatorQuadratic formula (Babylonian completing-the-square identity)Enter the three coefficients of ax ² + bx + c = 0 and this calculator returns both roots, the discriminant that decides whether…
Geometry & Trigonometry
- Triangle Area CalculatorThis calculator finds the area of any triangle by whichever route your measurements allow: base and perpendicular height, three…
- Circle Area CalculatorEnter whichever circle measurement you have — radius, diameter, circumference or even the area itself — and this…
- Pythagorean Theorem Calculatora² + b² = c² relates the three sides of any right triangle, and this calculator runs it in all three directions…
- 30-60-90 Triangle CalculatorA 30-60-90 triangle has its sides locked in the exact ratio 1 : √3 : 2, so one measurement gives you all of them with no…
- Sin Cos Tan CalculatorUnit-circle definitions of the circular functions (ISO 80000-2)Type an angle in degrees or radians and read all six trigonometric functions at once: sine, cosine and tangent plus their…
Calculus, Linear Algebra & Discrete Math
- Derivative CalculatorStandard differentiation rules (power, product, quotient, chain)Type a function of one variable and this calculator differentiates it symbolically, simplifies the result, and evaluates the…
- Indefinite Integral CalculatorStandard integration rules: power, substitution, by partsEnter a function and this calculator finds its antiderivative, splitting the integrand into terms and reporting which rule…
- Limit CalculatorEpsilon-delta definition of a limit, evaluated by numerical approachEnter a function and a point and this calculator approaches that point from both sides, dividing the step by ten at each stage…
- Partial Derivative CalculatorClairaut's theorem on the equality of mixed partialsType a function of x , y and z and this calculator differentiates it with respect to one variable at a time, holding the others…
- Newton-Raphson Method CalculatorNewton-Raphson iterationEnter a function and a starting guess and this calculator runs Newton-Raphson iteration until the step size falls below your…
Statistics & Probability
- Mean, Median, Mode & Range CalculatorDescriptive statistics (measures of central tendency)Paste a list of numbers and this calculator returns the four summary figures every statistics course starts with: the mean, the…
- Z-Score CalculatorStandard normal distribution (standardisation)A z-score says how many standard deviations a value sits above or below the mean. Enter the raw value, the mean and the…
- Probability Calculator (Single & Two Events)Kolmogorov probability axioms and the addition ruleGive this calculator the probabilities of two events and how they relate, and it returns every derived probability at once: the…
- Normal Distribution Probability CalculatorGaussian (normal) distributionEnter a mean, a standard deviation and one or two bounds, and this calculator returns the area under the normal curve: the…
- Confidence Interval Calculator for a MeanStudent's t distributionThis calculator builds a confidence interval for a population mean from three numbers you already have: the sample mean, the…
Physics: Mechanics, Waves & Thermodynamics
- Projectile Motion CalculatorTwo-axis constant-acceleration kinematics (vacuum trajectory)Enter a launch speed, a launch angle and — if the projectile does not start at ground level — a launch height. The calculator…
- Newton's Second Law (F = ma) CalculatorNewton's second law of motion; SI units per NIST SP 811Pick which of the three quantities you want, enter the other two, and this calculator solves F = ma for it. It also reports the…
- Work Done by a Force CalculatorMechanical work, W = F·d·cos θ (SI joule per NIST SP 811)Work in physics means force multiplied by the distance moved in the direction of that force, and this calculator gives it to…
- Torque CalculatorMoment of a force, τ = r × F; SI and customary torque units per NIST SP 811Torque is the turning effect of a force about an axis, and it depends on three things: how big the force is, how far from the…
- Hooke's Law Spring Force CalculatorHooke's law (linear elastic range)Enter any two of spring rate, deflection and force, and this calculator returns the third from Hooke's law, F = kx . It also…
Chemistry & Chemical Engineering
- Molar Mass CalculatorIUPAC standard atomic weights (abridged, 2021)Type a chemical formula and this calculator returns its molar mass in grams per mole, together with the mass each element…
- Molarity CalculatorIUPAC definition of amount concentration (mol/L)Molarity is moles of solute per litre of finished solution. This calculator works the relationship in all three directions: it…
- Chemical Equation BalancerConservation of mass (Lavoisier) solved as a linear null-space problemType an unbalanced equation such as C3H8 + O2 = CO2 + H2O and this returns the smallest set of whole-number coefficients that…
- Boyle's Law CalculatorBoyle's law (1662), the isothermal limit of the ideal gas lawBoyle's law says that for a fixed amount of gas held at constant temperature, pressure and volume are inversely proportional…
- pH & pOH CalculatorIUPAC pH definition, Kw = 1.0e-14 at 25 degCEnter any one of pH, pOH, [H + ], [OH − ], or the concentration of a strong acid or strong base, and this calculator…
Biology, Genetics & Clinical Lab
- Cell Doubling Time CalculatorExponential (Malthusian) growth modelEnter the cell density you seeded, the density you counted at harvest, and the hours in between. This calculator returns the…
- DNA / RNA Concentration from A260 CalculatorBeer–Lambert law with standard A260 conversion factors (Sambrook, Molecular Cloning)This calculator turns a 260 nm absorbance reading into the three numbers you actually need at the bench: concentration in…
- Punnett Square Probability CalculatorMendel's laws of segregation and independent assortmentType each parent's genotype the way you would write it on paper — Aa , AaBb , AaBbCc — and this calculator builds the whole…
- Anion Gap CalculatorSerum anion gap with Figge albumin correctionEnter a basic metabolic panel and this calculator returns the serum anion gap, the albumin-corrected gap, the delta gap, the…
- Body Surface Area (BSA) CalculatorMosteller and Du Bois formulasThis calculator returns body surface area in square metres from height and weight by all five formulas in routine clinical use…
Trades & engineering
Construction, Carpentry & Concrete
- Concrete Slab CalculatorASTM C94/C94MEnter the length, width and thickness of a slab and this calculator returns the concrete volume in cubic feet, cubic yards and…
- Concrete Block CalculatorASTM C90 units; ASTM C270 mortar; TMS 602 beddingThis calculator turns a wall dimension into a block order. Give it the length, height and nominal unit size and it returns the…
- Wall Stud Count CalculatorIRC R602 wood wall framingEnter a wall length, a height and an on-centre spacing and this calculator returns the full stick count: layout studs, the…
- Roof Pitch CalculatorIRC 2021 R905 slope limitsRoof pitch is written as rise in inches over a 12-inch run, but almost every calculation you need it for wants a different…
- Stair Rise & Run CalculatorIRC 2021 R311.7 / IBC 2021 1011Enter the total rise from finished floor to finished floor and this calculator splits it into equal risers, then returns the…
Electrical Trade & Electronics
- Ohm's Law CalculatorOhm's law and Joule's law (IEEE Std 280 quantity symbols)Pick the two quantities you already know — any two of voltage, current, resistance and power — and this calculator returns the…
- Capacitive Reactance CalculatorNEC 2023 Art. 460 · IEEE Std 18Enter a capacitance and a frequency and this calculator returns the capacitor's reactance in ohms, the current it draws from a…
- Wire Size & Ampacity CalculatorNEC 2023 (NFPA 70), Table 310.16 with 110.14(C), 240.4 and 310.15Enter the load, the conductor material and the conditions the conductor will live in, and this calculator returns the smallest…
- Three-Phase Power CalculatorBalanced three-phase AC power relations (IEEE Std 1459)Give this calculator the line-to-line voltage, the power factor, and any one of line current, kilowatts or kilovolt-amperes…
- Dwelling Load Calculation CalculatorNEC 2023 (NFPA 70) Article 220, Part IIIThis calculator runs the standard method dwelling load calculation from Article 220 of the National Electrical Code and returns…
HVAC, Refrigeration & Building Science
- Manual J Heating & Cooling Load CalculatorACCA Manual J 8th ed. (block load)This calculator runs a whole-house block load in the shape ACCA Manual J uses: conduction through each envelope assembly…
- Duct Size Calculator (Equal Friction & Velocity Method)ASHRAE / ACCA Manual D friction equationEnter the airflow a duct has to carry and the friction rate your design allows, and this calculator returns the round diameter…
- Room CFM Requirement CalculatorACCA Manual D room airflowThe airflow a room needs follows from one equation: sensible load divided by 1.08 times the temperature difference between the…
- Dew Point Calculator (from Temperature & RH)Magnus-Tetens with WMO coefficientsDew point is the temperature at which the air you are standing in becomes saturated, and it is the number that decides whether…
- Sensible Heat Formula CalculatorASHRAE Handbook—Fundamentals air-side sensible heat equationThis calculator solves the air-side sensible heat equation in whichever direction you need it: enter airflow and temperature…
Plumbing, Piping & Hydraulics
- Pipe Volume CalculatorRight-circular-cylinder volume; 231 in³ per US gallonEnter the inside diameter and length of a pipe run and this calculator returns how much liquid it holds — in US gallons…
- Water Supply Fixture Unit (WSFU) CalculatorIPC Appendix E (Hunter's fixture-unit method)Count your fixtures, and this calculator returns the cold, hot and combined water supply fixture unit totals, then converts the…
- Drainage Fixture Unit (DFU) CalculatorIPC Chapter 7 drainage sizing tablesCount the fixtures on the segment you are sizing and this calculator totals their drainage fixture units, then returns the…
- Sump Pump Size & Capacity CalculatorHazen-Williams (C = 150, PVC); Crane TP-410 equivalent lengthsMeasure how fast water rises in your sump pit with the pump unplugged, and this calculator turns that into the pump duty you…
- Total Dynamic Head (TDH) CalculatorHazen-Williams (AWWA practice)Total dynamic head is the whole job you are asking a pump to do, expressed as a height of water. It is the vertical distance…
Machining, Welding & Metal Fabrication
- Cutting Speed (SFM) CalculatorMachinery's Handbook cutting speed conventionCutting speed is the velocity of the cutting edge relative to the work, and it is the parameter that sets the temperature at…
- Drilling Speed & Feed CalculatorMachinery's Handbook drilling practiceDrilling needs four numbers and this calculator produces all of them: the spindle speed that puts the outside corner of the…
- Bolt Torque CalculatorSAE J429 / ISO 898-1 with the short-form torque equationTorque is not the thing you actually want from a bolt. What holds a joint together is preload — the tension stretched…
- ISO Hole & Shaft Fit Tolerance CalculatorISO 286-1 / ISO 286-2 (hole-basis limits and fits)A drawing that says ø40 H7/g6 is making four separate statements about size, and this calculator unpacks all of them…
- Gear Ratio & Output Speed CalculatorAGMA gear train conventionA gear train trades speed for torque, and the exchange rate is set entirely by tooth counts. This calculator takes up to three…
Automotive, Diesel & Motorsports
- Engine Displacement CalculatorSwept-volume definition (SAE J1349 engine displacement)Engine displacement is the total volume every piston sweeps in one full revolution of the crank, and it follows directly from…
- Volumetric Efficiency CalculatorIdeal-gas volumetric efficiency (Heywood)Volumetric efficiency tells you how completely each cylinder fills compared with its own swept volume. Enter your displacement…
- Horsepower from Torque CalculatorMechanical power definition, 1 hp = 33,000 ft·lbf/minPower is torque multiplied by rotational speed, and the constant 5,252 is the only thing standing between the two. Enter torque…
- Quarter Mile ET & MPH CalculatorFox and Huntington ET correlationsEnter race weight with the driver in the seat and flywheel horsepower, and this calculator predicts the elapsed time and trap…
- Carburetor CFM CalculatorFour-barrel CFM rated at 1.5 inHg, two-barrel at 3.0 inHgA carburettor has to flow the air the engine can actually swallow at peak power — no more, or velocity and signal…
Aviation, Aerospace & Marine
- Density Altitude CalculatorICAO Standard Atmosphere (ISO 2533)Density altitude is the altitude your aeroplane's wing, propeller and engine think they are at. Enter field elevation, the…
- Crosswind & Headwind Component CalculatorVector resolution; demonstrated crosswind per 14 CFR 23.2105 / CS-23A wind of "300 at 18 gusting 25" means nothing until you resolve it against the runway you intend to use. This calculator…
- Takeoff Distance CalculatorCAA Safety Sense correction factorsTake-off distances in a flight manual are demonstrated numbers: a new aeroplane, a test pilot, a dry level paved runway and a…
- Aircraft Weight & Balance CalculatorFAA-H-8083-1BEnter the weight and arm of every station on your aircraft and this calculator returns the loaded weight, the total moment and…
- Lift Equation CalculatorISA (ICAO Standard Atmosphere, 1993)This calculator solves the lift equation L = ½ρV²S·C L in any of its four directions: the lift a wing…
Home Improvement Projects & Renovation
- Home Renovation Budget CalculatorLine-item cost estimatingThis calculator turns a renovation into the five lines every estimator uses — materials, labour, fixtures and appliances…
- Home Project Duration CalculatorDeterministic scheduling with explicit floatLabour hours tell you how long the work takes. They tell you nothing about how long the project takes, because a renovation…
- Home Improvement ROI CalculatorCost-versus-value recoup analysisNo ordinary renovation returns more at resale than it costs. What a good one does is give a large part of the money back, so…
- Flooring Project Cost CalculatorASTM F710 subfloor preparationA flooring quote is four numbers pretending to be one: the material you order (which is more than the room, because of waste)…
- Renovation Contingency CalculatorRisk-based contingency framework (defined on this page)A flat ten per cent contingency treats a 1910 house with plaster walls and knob-and-tube wiring the same as a 2015 house with…
Industrial, Logistics & Plant Operations
- Pallet Pattern Calculator (Cases per Pallet & Cube Utilization)GMA 48 × 40 in pallet footprint; ISO 3676 unit load sizesGive this calculator your case dimensions, your pallet footprint and the maximum height a loaded pallet may reach, and it…
- OEE Calculator (Overall Equipment Effectiveness)Nakajima TPM definition of OEE; SEMI E79 equipment efficiency measurementOEE multiplies three rates that each answer a different question: did the machine run when it was supposed to, did it run at…
- API Gravity Calculator (Specific Gravity, lb/gal & bbl per Ton)API MPMS Chapter 11.1 volume correction; API gravity defined at 60/60 °FAPI gravity is an inverted density scale built so that heavier oil gets a lower number and 10 °API is exactly the density of…
- OSHA Incident Rate Calculator (TRIR, DART & LTC)OSHA 29 CFR Part 1904 recordkeeping; incidence rates per 200,000 hoursEvery OSHA incidence rate is the same calculation with a different numerator: count the cases, multiply by 200,000, divide by…
- Janitorial Cleaning Time Calculator (Production Rates)Production-rate estimating; ISSA Cleaning Times methodologyJanitorial estimating is production-rate arithmetic: divide each surface's area by the square feet an operator covers per hour…
Technology & media
Computing, IT, Networking & Security
- IPv4 Subnet Calculator (CIDR)RFC 4632 (CIDR), RFC 950, RFC 1918Give this calculator an IPv4 address and a prefix length and it resolves the address to the block it belongs to: the network…
- Data Transfer Time CalculatorDecimal SI and IEC 80000-13 binary prefixesEnter how much data you have to move and how fast the link is, and this calculator returns the elapsed time in days, hours…
- RAID Capacity CalculatorSNIA Common RAID Disk Data Format; IEC 80000-13 binary prefixesEnter your drive count, drive size and RAID level and this calculator returns the capacity you can actually write to — in…
- Cloud VM Monthly Cost Calculator730-hour month convention (8,760 ÷ 12)Cloud instances are quoted by the hour and budgeted by the month, and the conversion hides two traps. The first is that a month…
- Uptime SLA Downtime CalculatorAvailability = uptime ÷ agreed service timeEnter an availability target and this calculator tells you exactly how many minutes of downtime it buys you in the period you…
AI, LLM & Machine Learning Engineering
- LLM API Token Cost CalculatorPer-million-token billing conventionLarge-language-model APIs bill per million tokens, with output tokens costing several times more than input tokens and cached…
- LLM GPU VRAM Requirement CalculatorThis calculator adds up the four things that occupy GPU memory when you run a language model: the weights, the KV cache, the…
- Transformer Parameter Count CalculatorGive this calculator the six numbers from a model config — hidden size, layer count, feed-forward width, attention heads…
- RAG Chunking CalculatorFixed-size sliding-window chunkingThis calculator answers the two questions that decide a retrieval pipeline's shape: how many chunks your corpus becomes at a…
- F1 Score & Classification Metrics CalculatorF-measure (van Rijsbergen, 1979)Enter the four cells of a confusion matrix and this calculator returns every headline metric a model review asks for…
Cloud, SaaS & IT Spend
- Reserved vs On-Demand Break-Even CalculatorCommitted-use discount break-even analysisA cloud commitment is not a discount. It is a purchase of a fixed number of instance-hours at a lower unit price, billed…
- SaaS Seat Utilization & Shelfware CalculatorITAM software licence optimisation (ISO/IEC 19770-1)Seats bought are not seats used, and the gap is billed annually whether anyone logs in or not. This calculator turns three…
- Build vs Buy Software CalculatorDiscounted cash flow comparison of alternativesBuild-versus-buy decisions go wrong on the second line, not the first. Development cost is estimated carefully and maintenance…
- SLA Credit vs Actual Loss CalculatorA service credit is a discount on next month's invoice. Your loss during an outage is revenue that did not happen. This…
- Spot Instance Savings & Interruption CalculatorExponential interruption model (memoryless hazard)A 70% spot discount is not a 70% saving if the job restarts twice. This calculator prices spot capacity the way it actually…
Creator Economy, Streaming & Content Production
- YouTube Ad Revenue Calculator (RPM & CPM)CPM-to-RPM revenue identityThree numbers stand between an advertiser's CPM and the money in your account: the share of your views that ever carry an ad…
- Newsletter Revenue Calculator (Paid & Sponsored)Dual-line subscription and CPM modelNewsletters make money two ways at once, and the two are priced on completely different bases. Subscription income depends on…
- Livestream Bitrate & Upload Speed CalculatorBits-per-pixel encoding estimate (H.264/HEVC/AV1)A stream fails for one of two reasons: the bitrate is too low for the picture, or it is too high for the connection. This…
- Sponsorship Rate Calculator (Creator Pricing)CPM and engagement cross-check pricingThere are two defensible ways to price a sponsored integration, and quoting only one of them is how creators end up either…
- Channel Monetisation Threshold CalculatorTwo-threshold eligibility projectionMost monetisation programmes gate you behind two independent thresholds at once — a subscriber count and a quantity of watch…
Music Theory, Audio Engineering & Instruments
- Note to Frequency Calculator12-tone equal temperament; A4 = 440 Hz per ISO 16Every note in twelve-tone equal temperament is the reference pitch multiplied by a power of the twelfth root of two. Give this…
- Delay & Reverb Time CalculatorTempo defined as quarter notes per minuteA delay that is not locked to the tempo fights the groove; one that is locked disappears into it. The arithmetic is one…
- Decibel Addition CalculatorEnergy summation of levels; geometric spreading per ISO 9613-2Decibels are logarithms, so they do not add. Two machines at 85 dB each do not make 170 dB, and they do not make 85 dB either -…
- String Tension CalculatorMersenne-Taylor law; unit-weight form used by string manufacturersString tension is set by three things and nothing else: how heavy the string is per inch, how long the vibrating span is, and…
- Cents & Interval CalculatorEllis cent, 1200 per octave; 12-tone equal temperamentA cent is one hundredth of an equal-tempered semitone and one twelve-hundredth of an octave, defined logarithmically so that…
Home & everyday
Everyday Life & Household
- Tip CalculatorPre-tax gratuity conventionEnter the check subtotal, your local sales tax and the percentage you want to leave, and this calculator returns the tip, the…
- Sale Price & Discount CalculatorFTC Guides Against Deceptive Pricing (16 CFR 233)Enter what you know and this calculator fills in the rest of the deal. Give it an original price and a percent off — plus a…
- Subscription Cost Audit CalculatorFuture value of an ordinary annuityRecurring charges are designed to be invisible: each one is small, each one renews silently, and no statement ever shows you…
- Road Trip Drive Time & Arrival CalculatorEnter the distance and the average speed you expect to hold and this calculator returns three numbers a route app hides from…
- Electricity Bill CalculatorTiered (inclining-block) residential tariff structureEnter the kilowatt-hours on your meter and the rates from your tariff sheet, and this calculator rebuilds your electric bill…
Cooking, Baking & Brewing
- Recipe Scaling CalculatorRecipe conversion factor (RCF) method, standard culinary practiceEnter the yield your recipe was written for and the yield you need, and this calculator returns the recipe conversion factor —…
- Baker's Percentage CalculatorBaker's percentage (flour = 100%)Baker's percentage expresses every ingredient in a bread formula as a percentage of the total flour weight, with flour itself…
- Turkey Cooking Time CalculatorUSDA FSIS roasting guidanceEnter the weight of your bird, whether it is stuffed, and the time you want to carve. This calculator returns the roasting time…
- Brine Salt Percentage CalculatorEquilibrium brining and the salometer scaleEnter the meat you are brining, the water you will cover it with, and the strength you want, and this calculator returns the…
- Food Cost Percentage CalculatorUniform System of Accounts for Restaurants (USAR)Food cost percentage is the share of your food sales that the food itself consumed. This calculator builds it the way an…
Health, Fitness & Nutrition
- BMI CalculatorWHO adult BMI classificationBody mass index compares your weight with your height on a single scale, and it is the number every screening tool, insurance…
- BMR CalculatorMifflin-St Jeor equation (1990)Basal metabolic rate is the energy your body spends doing nothing — running your heart, brain, kidneys and liver while you lie…
- Macro Split CalculatorAtwater energy factors (4/4/9 kcal per gram) and IOM acceptable macronutrient distribution rangesA calorie target tells you how much to eat; a macro split tells you what. This calculator turns a daily calorie figure and a…
- One Rep Max CalculatorEpley, Brzycki, Lombardi, Lander and O'Conner repetition-maximum equationsA one rep max is the heaviest load you can lift once with good technique, and estimating it from a set you have already done is…
- Running Pace CalculatorPace = time ÷ distancePick what you want to solve for — pace, finish time or distance — enter the other two, and this calculator returns your pace in…
Unit & Measurement Conversion
- Millimeters to Inches CalculatorInternational inch, 1959 (1 in = 25.4 mm exactly)Convert millimeters, centimeters or meters into decimal inches and the nearest usable fraction, or run an inch dimension back…
- Square Feet to Square Meters CalculatorInternational Yard and Pound Agreement (1959)Floor areas cross borders constantly — a listing in square feet, a specification in square meters, a flooring quote in…
- Kilograms to Pounds CalculatorInternational Yard and Pound Agreement (1959): 1 lb = 0.45359237 kg exactlyOne pound is exactly 0.45359237 kilograms. That single definition, agreed internationally in 1959, is all this calculator…
- Celsius to Fahrenheit CalculatorSI (BIPM) / ITS-90Enter a temperature in any of the four scales in common use and this calculator returns the other three, showing the arithmetic…
- BTU to kWh CalculatorISO 80000-5 / NIST SP 811Energy units are all fixed multiples of the joule, so converting a gas bill in therms into the kilowatt-hours your heat pump…
Time, Date, Navigation & Astronomy
- Day of the Week CalculatorZeller's congruence (1882); ISO 8601 weekday numberingEnter any date and this calculator returns the weekday, the ISO 8601 weekday number, the day of the year and the Julian Day…
- Time Duration CalculatorISO 8601 time-of-day and duration conventionsEnter a start time and an end time and this calculator returns the elapsed span in hours, minutes and seconds, in decimal…
- Unix Timestamp Converter CalculatorPOSIX.1-2017 seconds since the EpochPaste an epoch value and get the UTC date, your local date, the ISO 8601 string and the day of the week; or switch direction…
- Sunrise & Sunset Time CalculatorNOAA solar position algorithm (after Meeus, Astronomical Algorithms)Enter a latitude, longitude, date and UTC offset and this calculator returns sunrise, sunset, solar noon, day length and the…
- Moon Phase CalculatorMeeus, Astronomical Algorithms, chapters 48 and 49Give this calculator any date and time and it returns the Moon's age in days since the last new moon, the percentage of the…
Education, Grading & Test Scores
- GPA Calculator4.0 quality-point scale (AACRAO transcript convention)Enter each course as a letter grade and its credit hours and this calculator returns your term grade point average the way a…
- Test Grade Percentage CalculatorPercentage grading with conventional 90/80/70/60 letter bandsEnter points earned out of points possible — or just the number of questions marked wrong — and this calculator returns the…
- Class Average CalculatorDescriptive statistics (population standard deviation)Paste a set of scores and this calculator returns everything a teacher needs to describe an assessment: the mean, the median…
- SAT Score Calculator (Raw to Scaled)College Board 200-800 section scaleEnter how many questions you answered correctly in each SAT section and this calculator returns a scaled score from 200 to 800…
- IQ Percentile & Rarity CalculatorDeviation IQ, normal distributionA modern IQ score is a standard score, not a ratio of ages. It says how far above or below the population mean you sit…
Professional Licensing & Applied Exam Math
- Mohr's Circle & Principal Stress CalculatorPlane-stress transformation (Cauchy)Give this calculator a plane-stress state — the two normal stresses σ x and σ y and the shear stress τ xy acting on a small…
- Bearing to Azimuth Converter CalculatorQuadrant bearing / whole-circle azimuth conventionEnter a quadrant bearing such as N 45°30′00″ E, or an azimuth measured clockwise from north, and this converter returns the…
- Insulin Correction Dose & Carb Ratio CalculatorRule of 1800 / 1500 and Rule of 500This calculator derives the two numbers intensive insulin therapy runs on — the insulin sensitivity factor (how far one unit…
- Alligation Alternate CalculatorAlligation alternate; USP <795> compounding practiceAlligation answers one question: you have a stronger preparation and a weaker one, you need a specific strength in between, so…
- Veterinary Fluid Therapy Rate CalculatorAAHA/AAFP Fluid Therapy Guidelines for Dogs and CatsEnter species, body weight and estimated percent dehydration and this calculator returns the three components of a fluid plan —…
All 14 professional licensing & applied exam math calculators →
Sports, Games, Gambling Odds & Hobbies
- Batting Average CalculatorMLB Official Baseball Rules, Rule 9.22Enter hits and at-bats and this calculator returns batting average to three decimal places exactly as an official scorer would…
- True Shooting Percentage CalculatorBasketball Reference / Dean Oliver shooting-efficiency definitionsTrue shooting percentage measures scoring efficiency across all three ways to score — two-pointers, three-pointers and free…
- Golf Handicap Index Calculator (World Handicap System)USGA/R&A Rules of Handicapping (World Handicap System), 2024 revisionA World Handicap System Index is the average of the lowest 8 Score Differentials in your most recent 20 rounds — not the…
- Elo Rating Change CalculatorFIDE Rating RegulationsEnter your rating, your opponents' ratings and how each game finished, and this calculator returns your expected score, the…
- Betting Odds Converter & Implied Probability CalculatorEnter a price in any format - American moneyline, decimal, fractional or Hong Kong - and this calculator returns the other…
Crafts, Textiles, 3D Printing & Photography
- Yarn Yardage & Skeins CalculatorArea-density (yards per square inch) methodThis calculator turns a swatch into a shopping list. Measure your swatch, tell it how much yarn went into it, give it the…
- Fabric Yardage CalculatorCut-length nesting method (usable width after selvedge)Tell this calculator the size of your pattern piece, how many you need, and how wide your fabric is, and it works out how many…
- Screen Printing Pricing CalculatorCost-plus quoting on a target gross marginThis calculator builds a screen printing quote the way a shop's books do: blanks, screen setup, ink, press time at your labour…
- Resin Mold Volume & Mixing CalculatorMix ratio by weight or by volume, per the resin data sheetTwo questions decide whether a resin pour succeeds: how much to mix, and how to split it between the two components. This…
- Gold Karat & Alloy Mixing CalculatorFTC Jewelry Guides, 16 CFR Part 23Karat is a ratio, not a grade: it is the number of parts of gold in 24 parts of metal by weight. This calculator converts…
Agriculture, Livestock & Landscaping
- Seeding Rate per Acre CalculatorPure live seed (PLS) basis — AOSA/AOSCA seed labelling conventionsGive this calculator the stand you are aiming for and it returns the seed you actually have to buy: pounds per acre, total…
- Fertilizer NPK Requirement CalculatorGuaranteed analysis labelling (AAPFCO Official Publication)A soil test tells you to apply 150 pounds of nitrogen, 60 of P 2 O 5 and 60 of K 2 O per acre. It does not tell you how much…
- Sprayer Calibration (Gallons per Acre) Calculator1/128-acre catch methodThis calculator tells you what your boom sprayer is actually putting out, in gallons per acre, rather than what the rate…
- Irrigation Run Time CalculatorIrrigation Association audit methodThis calculator answers the only irrigation question most people actually have: how many minutes should this zone run? Give it…
- Cattle Weight Calculator (Heart Girth Tape)Girth-and-length rule (Schaeffer's formula)Wrap a tape around the animal just behind the front legs, measure from the point of the shoulder to the pin bone, and this…
Energy, Solar, Sustainability & Environment
- Solar System Size (kW) CalculatorNREL PVWatts sizing methodEnter the kWh figure from your electric bill and this calculator returns the DC array size in kilowatts needed to hit your…
- Off-Grid Daily Load Audit (Watt-Hours) CalculatorEvery off-grid, RV and marine solar design starts with one number: the watt-hours your loads consume in a day. This calculator…
- Solar Panel Payback Period CalculatorDiscounted cash flow analysisThis calculator returns the year your solar system finishes paying for itself, on two different definitions. Simple payback…
- Wind Turbine Power Output CalculatorWind power equation P = ½ρAv³Cp; ISA atmosphere for air densityThis calculator applies the wind power equation — half the air density times swept area times the cube of wind speed, scaled by…
- Fuel Energy Content (BTU) Converter CalculatorEIA higher heating values (HHV)Fuels are sold in a dozen incompatible units — cubic feet, ccf, therms, gallons, cords, tons, kilowatt-hours — and none of them…
Ranked by our own editorial priority and the order each subject lists its calculators in — not by measured traffic. See how this site is put together.