Math Calculators

Percentage calculator that finds what X percent of a number is, like 15% of 200, with the working shown. Quick answers for tips, tests and discounts.

Percentage change calculator: compare two numbers to get the percent increase or decrease and the raw difference, with the formula and steps shown.

Average calculator for any list of numbers. Paste your values to get the mean, median, mode, sum, count and range in one step. Free, no sign-up.

Ratio calculator that reduces any ratio to lowest terms and shows it as a decimal, like 16:9 to 1.78. Handy for screens, recipes and scale models.

GCD and LCM calculator: find the greatest common divisor and least common multiple of two integers at once, with the math behind each answer.

Rounding calculator that rounds any number to the decimal places you choose, from whole numbers to 10 places. Instant, exact and free to use.

Words to numbers converter: type a number in English words, like two thousand five hundred, and get the digits. Handles decimals and negatives too.

Numbers to words converter: type a number like 1234 and get it spelled out in English words, including decimals and negative values.

Roman numeral converter that works both ways: turn a number like 2024 into MMXXIV, or a Roman numeral back into a number.

Find what percent one number is of another, for example 30 is what percent of 200. Shows the percentage and the working.

GPA calculator on the 4.0 scale. Enter each course grade and its credit hours to get your weighted grade point average and total credits.

Fraction calculator to add, subtract, multiply or divide two fractions. Get the answer as a simplified fraction, a mixed number and a decimal.