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The most-searched arithmetic tools on the web: taking a percent of a number, comparing two numbers as a percent, and working…
Tools for reducing ratios, solving proportions by cross multiplication, and splitting a total according to a ratio. Heavily used…
Exact rational arithmetic and number-form conversion: the four fraction operations, reducing, mixed numbers, fraction/decimal…
Powers, radicals, logarithms and scientific notation — the operations that turn up in every algebra course and in every…
Deterministic solvers for the equation types assigned in Algebra 1 through college algebra: linear, quadratic, cubic…
Divisibility, primes, GCD/LCM, modular arithmetic and base conversion — the toolkit for discrete-math courses, cryptography…
Arithmetic and geometric progressions, famous sequences, factorials and counting formulas. Assigned constantly in algebra and…
Linear algebra and complex arithmetic tools used in engineering statics, computer graphics, control systems, electrical phasor…
Most used in 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…
- Percentage Change CalculatorRelative change on the earlier value as basePercent change measures how far a value has moved relative to where it started. Enter the earlier figure and the later figure…
- Percentage Increase & Decrease CalculatorMultiplicative percentage adjustmentApplying a percentage is a multiplication, not an addition. To raise a value by 20% you multiply by 1.20; to cut it by 20% you…
- 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…
- Multiplying Fractions CalculatorFundamental rule of fraction multiplicationMultiplying fractions is the easiest of the four fraction operations: multiply the tops, multiply the bottoms, reduce. No…
- Dividing Fractions CalculatorDivide one fraction or mixed number by another and get the exact quotient in lowest terms, as a mixed number, and as a decimal…
- Simplifying Fractions CalculatorEuclidean algorithm (Euclid, Elements VII.1–2)Enter any numerator and denominator and this calculator reduces the fraction to lowest terms, shows the greatest common divisor…
- Mixed Number to Improper Fraction CalculatorThis calculator converts in both directions at once. Enter a mixed number such as 3 1/2 and it returns the improper fraction…
- Fraction to Decimal CalculatorEnter a numerator and a denominator and this calculator performs the long division exactly. It reports the decimal in full —…
- Significant Figures CalculatorASTM E29 significant digits practiceType a measured value exactly as it is written and this calculator tells you how many significant figures it carries, rounds it…
- Exponent CalculatorLaws of exponentsAn exponent is repeated multiplication, and everything else about exponents follows from keeping that idea consistent. This…