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Percentages, fractions, finance, geometry, and more. Fast, free, and no sign-up required.

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Popular calculators

Percentage Calculator
Calculate percentages instantly: find X% of a number, what percent one number is of another, or apply a percentage increase or decrease.
Fraction Calculator
Add, subtract, multiply, and divide fractions. Simplify results and convert between mixed numbers and improper fractions.
Mortgage Calculator
Estimate your monthly mortgage payment based on loan amount, interest rate, and loan term.
BMI Calculator
Calculate your Body Mass Index (BMI) from height and weight, with WHO category classification.
Compound Interest Calculator
See how your money grows with compound interest. Enter principal, rate, compounding frequency, and time.
Standard Deviation Calculator
Calculate sample and population standard deviation, variance, and mean for any dataset.