Math Calculators
Tools for the arithmetic and algebra that turns up at school, at work and around the house. Fractions are handled exactly, and every result comes with its working.
Choosing the right tool
Percentage questions come in three forms — finding a part, a percentage or a whole — and the percentage calculator handles all three. For changes over time use the increase or decrease calculators; for comparing two equal-status values use percentage difference.
Fractions, ratios and the GCF are closely linked: simplifying 18/24 or 18 : 24 both come down to dividing by the greatest common factor, 6. The math reference tables collect the most useful equivalents in one place.
Percentages
From a quick “what is 15% of 80” to comparing two values fairly.
- Percentage CalculatorFind X% of a number, what percent one number is of another, or the whole from a part.
- Percentage Increase CalculatorPercentage growth between two values, or a value increased by a given percent.
- Percentage Decrease CalculatorHow much a value has fallen in percent, or a value reduced by a percentage.
- Percentage Difference CalculatorCompare two values relative to their average, with percentage change both ways.
- Percent Error CalculatorHow far a measured or estimated value is from the accepted value, in percent.
Fractions, ratios and proportions
Exact fraction arithmetic with results in lowest terms.
- Fraction CalculatorAdd, subtract, multiply, divide and simplify fractions and mixed numbers.
- Fraction to DecimalConvert any fraction or mixed number to a decimal, with repeating digits marked.
- Decimal to FractionTurn a decimal into an exact fraction, or the closest fraction with a limited denominator.
- Ratio CalculatorSimplify a ratio to lowest terms or divide a total in a given ratio.
- Proportion CalculatorSolve for the missing value in A/B = C/D using cross-multiplication.
Factors and primes
Number theory tools that also power fraction simplification.
- Factor CalculatorList every factor and factor pair of a whole number.
- GCF CalculatorGreatest common factor (GCD/HCF) of two or more whole numbers.
- LCM CalculatorLeast common multiple of two or more whole numbers, with the method.
- Prime Number CheckerCheck whether a number is prime and find the nearest primes.
- Prime FactorizationBreak a number into prime factors with exponents and a division ladder.
Powers, roots and notation
- Exponent CalculatorRaise a number to any power, including negative and fractional exponents, or take nth roots.
- Square Root CalculatorSquare roots as decimals and in simplified radical form, e.g. √72 = 6√2.
- Cube Root CalculatorCube roots of positive and negative numbers, with simplified radical form.
- Logarithm CalculatorLog base 10, natural log, log base 2 or any base — plus antilogarithms.
- Scientific NotationConvert numbers to scientific, E and engineering notation and back.
- Rounding CalculatorRound to decimal places, significant figures or the nearest multiple, with five rounding rules.
- Scientific CalculatorTrig, logs, powers, roots and factorials with correct order of operations.