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 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 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.
n! = n × (n-1) × (n-2) × ... × 2 × 1. For example, 5! = 5 × 4 × 3 × 2 × 1 = 120. By definition, 0! = 1.
JavaScript handles numbers up to 2^53. Factorials grow very fast — 18! is the largest exact integer factorial. Beyond that, the tool shows approximate scientific notation.
Yes. The tool displays the full expansion (e.g., 6! = 6 × 5 × 4 × 3 × 2 × 1 = 720) so you can follow the calculation.
Permutations, combinations, probability calculations, Taylor series, binomial distribution, and various mathematical formulas in statistics and algebra.
Yes. All calculations run in your browser. No data is transmitted.
Permutation Calculator
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.
Combination Calculator
Compute nCr combinations and nPr permutations with factorial steps shown. Count 5-card poker hands (2,598,960) correctly — free, local, no signup.
Last updated October 2026