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Binary address math behind every network design and CCNA/Network+ exam question: CIDR subnetting, masks, host counts, VLSM…
Link sizing and performance math for WAN/LAN capacity planning: transfer times, per-user bandwidth budgets, speed unit…
Capacity and performance math for disk arrays and data protection: RAID usable space and IOPS penalties, decimal vs binary…
Sizing and spend math for cloud and container platforms: instance and egress bills, LLM API token costs, vCPU and concurrency…
Availability engineering math used by SREs, service desks and DR planners: nines to allowed downtime, MTBF/MTTR, redundancy…
Quantitative security math: password and key strength, brute-force timelines, hash collision probability, CVSS scoring and…
Bitrate, resolution and color math for video, audio, image and front-end work, including WCAG accessibility contrast and pixel…
Core CS and application-engineering formulas taught in architecture, algorithms and database courses and used daily by…
Hardware and transaction economics for miners and on-chain users: mining revenue against power cost, difficulty-based block…
Most used in 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…
- Subnet Mask to CIDR Converter CalculatorRFC 4632 (CIDR), RFC 1878Routers, firewalls, cloud consoles and operating systems all describe the same 32-bit value in different notations: /26…
- Hosts per Subnet CalculatorRFC 4632 (CIDR), RFC 3021 (/31 links)Enter a prefix length and this calculator tells you how many addresses the block contains and how many of them you can actually…
- 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…
- Mbps to MB/s Speed Converter CalculatorIEC 80000-13 (binary prefixes), SI decimal prefixesYour ISP sells megabits per second. Your browser reports megabytes per second. They differ by a factor of eight, which is why a…
- Network Bandwidth Requirement CalculatorITU-T G.711 / G.729 payload rates; IETF RFC 3550 (RTP)A circuit is sized for the busiest minute of the busiest day, not for the average. This calculator builds that peak from the…
- 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…
- RAID IOPS & Write Penalty CalculatorSNIA storage performance terminologyAn application asking for 5,000 IOPS does not put 5,000 operations on your disks. Every small write to a parity RAID set costs…
- 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…
- MTBF, MTTR & Availability CalculatorIEC 60050-192 dependability termsEnter how many hours your equipment actually ran, how many times it failed, and how long the repairs took. You get mean time…
- Password Entropy CalculatorNIST SP 800-63BEntropy measures how many equally likely passwords an attacker has to search, expressed as a power of two. A password drawn…