Calculate anything. Fast.

Free online calculators for finance, health, math, and everyday life. Accurate, fast, and beautifully designed.

Browse by

Calculate exact age in years, months, days, hours. See your age on other planets, countdown to next birthday, and compare two people.

Calculate your Body Mass Index in metric or imperial units and see your category.

Calculate compound interest with monthly contributions. See how your money grows over time.

Calculate monthly mortgage payment, total interest, and amortization schedule. Compare Price vs. SAC systems.

Calculate percentages three ways: what is X% of Y, X is what percent of Y, and percentage change.

Calculate tip amount, total bill, and per-person split — with smart rounding and regional tipping guidance.