Math Calculators
Work out percentages, simplify fractions and ratios, summarize data and measure shapes.
12 calculators · instant answers
Featured calculators
A handpicked starting point for everyday calculations.
Percentages
Find a portion, compare values or apply an increase or discount.
Fractions
Calculate exact fractions and move between fractional and decimal notation.
Fraction Calculator
Add, subtract, multiply or divide two fractions and reduce the answer to simplest form. Enter whole-number numerators and nonzero denominators.
↗FractionsDecimal to Fraction Calculator
Express a finite decimal as a simplified fraction.
↗FractionsFraction to Decimal Calculator
Convert a fraction into decimal notation.
↗Ratios
Simplify relationships and solve a missing value in a proportion.
Statistics
Describe the centre and spread of a set of numbers.
Average Calculator
Find the mean, median, mode and range of your numbers. Compare the centre of a dataset with its smallest and largest values.
↗StatisticsStandard Deviation Calculator
Measure the spread of a dataset using population or sample standard deviation. See variance and the mean alongside the result.
↗Geometry
Calculate dimensions for ideal shapes with consistent units.
Choose the formula that matches your question
Keep measurement units consistent and identify the baseline before entering numbers. An exact fraction, a rounded decimal and a percentage can describe the same quantity in different ways.
- Percentage calculator finds a portion or applies a discount; percentage change compares an original value with a new one.
- Fraction calculator performs arithmetic on fractions; the decimal converters change the way a single number is represented.
- Average calculator describes the centre of a dataset; standard deviation describes how widely values are spread.
- Area calculator measures a flat shape in square units; volume measures a solid in cubic units.
Check each tool’s formula, examples and limitations. Read how we check calculations or report an error.