Free maths calculators

Every calculator here shows its working, so you can check your own method instead of just copying an answer.

Fraction CalculatorAdd, subtract, multiply and divide fractions, simplified with every step.Percentage CalculatorFind a percentage of a number, a percentage change, or the original amount.Quadratic Equation SolverSolve ax² + bx + c = 0 and see the discriminant, roots and vertex.Mean, Median and Mode CalculatorPaste a list of numbers for the averages, range and standard deviation.Area and Perimeter CalculatorArea and perimeter for squares, rectangles, triangles, circles and parallelograms.Unit ConverterConvert length, weight, temperature, volume and speed.GCF and LCM CalculatorGreatest common factor and lowest common multiple with prime factors.Pythagorean Theorem CalculatorFind a missing side of a right-angled triangle, plus area, perimeter and angles.

How to get the most out of these tools

A calculator is best used as a second pair of eyes. Do the question on paper first, then run the same numbers here. If the answers match, you can move on with confidence. If they do not, read the working underneath the result: it usually points straight to the line where something slipped, whether that is a sign, a common denominator or a misplaced decimal point.

All eight calculators run in your browser, so nothing you type is sent anywhere, and they work on school Chromebooks, tablets and phones. If you are stuck on the idea behind a topic rather than the arithmetic, our study guides explain the method in plain language with worked examples.