Scientific Calculator
Full scientific calculator with trig, logs and powers.
OpenFraction Calculator
Add, subtract, multiply and divide fractions, simplified.
OpenPercentage Calculator
Percentage of a number, percent change and more.
OpenRandom Number Generator
Generate random numbers in any range.
OpenTriangle Calculator
Area, perimeter and angles of a triangle from its sides.
OpenStandard Deviation Calculator
Mean, variance and standard deviation of a data set.
OpenAverage (Mean) Calculator
Mean, median, sum and count of a list of numbers.
OpenLCM & HCF Calculator
Lowest common multiple and highest common factor of numbers.
OpenRatio Calculator
Simplify ratios and solve for a missing value.
OpenMath Calculators — free and easy to use
Percentages, fractions, statistics, geometry and a scientific calculator. Every tool here runs instantly in your browser, needs no sign-up, and works on any phone or computer. Pick a tool above to get started, enter your values, and read a clear result with a full breakdown.
All results are estimates to help you plan — for money, tax and official matters, confirm the figures with the relevant authority.