Calculate the remainder of division (a mod b). Shows quotient, remainder, full division expression, and negative dividend semantics. Numbers never leave your device — every calculation runs locally in your browser.
Calculate the factorial of any number (n!). Handles large numbers and shows the full multiplication sequence. Numbers never leave your device — every calculation runs locally in your browser.
Calculate the number of ways to arrange k items from n items (nPr). Shows the step-by-step permutation calculation. Numbers never leave your device — every calculation runs locally in your browser.
Calculate the exact duration between two times. Handles overnight time spans and displays results in hours, minutes, and seconds. Numbers never leave your device — every calculation runs locally in your browser.
Calculate Annual Recurring Revenue from subscription revenue, expansion revenue, and churn. Essential for SaaS businesses tracking growth. Numbers never leave your device — every calculation runs locally in your browser.
Calculate customer churn rate by dividing customers lost by total customers. Monitor retention health for your subscription business. Numbers never leave your device — every calculation runs locally in your browser.
Modulo (mod) returns the remainder after division. For example, 17 mod 5 = 2 because 17 = 5 × 3 + 2. It's used in cryptography, hash functions, clock arithmetic, and array indexing.
JavaScript's % truncates the quotient toward zero, so -7 % 3 = -1. Python floors toward negative infinity, so -7 % 3 = 2. Both are valid — they just define 'remainder' differently. This tool shows both results when they differ.
It shows the complete division expression: dividend ÷ divisor = decimal, the integer quotient, and the remainder calculation (dividend − divisor × quotient = remainder). This helps verify the result step by step.
Common uses: checking if a number is even/odd (n % 2), cycling through array indices (i % length), implementing hash tables, clock arithmetic (hours % 12), and modular exponentiation in cryptography.
Greatest Common Factor Calculator
Find the greatest common factor (GCF/GCD) of number sets via Euclidean algorithm with steps. Reduce 48:180 to 4:15 correctly — free, local, no signup.
Rounding Calculator
Round numbers using 5 modes: round half up, banker's rounding, floor, ceil, and truncate. Shows step-by-step explanation with the digit being rounded. Numbers never leave your device — every calculation runs locally in your browser.
Last updated October 2026