Math Calculators
A free collection of online math calculators for percentage, fractions, GCD/LCM, average and prime factorization.
Math Calculator is a free collection of browser-based math tools — no sign-up, no install — that instantly compute percentages, fractions, GCD/LCM, average & standard deviation, and prime factorization.
Every calculation runs locally in your browser; your inputs are never sent to or stored on a server.
All Math Calculators
Percentage Calculator
Find X% of a number, percentage change, and part/whole ratio across multiple modes.
Fraction Calculator
Add, subtract, multiply and divide fractions and simplify to lowest terms.
GCD & LCM Calculator
Find the greatest common divisor (GCD) and least common multiple (LCM) of several integers at once.
Average & Standard Deviation
Enter a data set to compute mean, median, variance and standard deviation.
Prime Factorization & Prime Test
Factor an integer into primes and check whether a number is prime.
Math Guides
Why use Math Calculator
- Free & install-free — Use it straight from your browser, no account or app required.
- No data collection — Every calculation runs in your browser; inputs are never sent to a server.
- Accurate math — Uses standard formulas such as the Euclidean algorithm, lowest-terms reduction and standard deviation.
- Formulas shown — Each calculator displays the formula and the steps used to reach the result.
All results are for reference. For exams, assignments and other important uses, please verify the working yourself.
Last updated: 2026-06-25