Free tools
Math & graphing tools
Calculators, fractions, ratios, unit conversions, equation plotting and chart digitizing.
9 tools · no sign-up · no uploads
Percentage
Work out a percentage of a number, compare two numbers, measure change, or add a markup or discount.
Open toolUnit converter
Convert length, weight, temperature, volume, area, speed, time, energy, pressure and data in US and metric units.
Open toolRandom numbers
Generate secure random integers or decimals, with ranges, counts and an optional no-duplicates rule.
Open toolScientific calculator
Evaluate expressions with trigonometry, logarithms, powers, factorials and memory, in degree or radian mode.
Open toolPlot digitizer
Extract data points from a chart image by calibrating the axes, clicking points and exporting a CSV.
Open toolEquation plotter
Graph y = f(x), compare several equations at once, adjust the view window and export sampled points as CSV.
Open toolFractions
Add, subtract, multiply and divide fractions or mixed numbers, simplify the result and see the decimal form.
Open toolRatios
Simplify a ratio, list equivalent ratios, solve a proportion for a missing term and split a total in a given ratio.
Open toolGPA
Turn letter grades or percentages into a credit-weighted semester GPA, and merge prior coursework for a cumulative GPA.
Open toolLooking for something else? Browse all 36 tools.
All toolsRelated reading
The context behind these tools.
Fractions explained, from pizza to percentages
Numerators, denominators, equivalent fractions, addition, multiplication and the common mistakes that make fractions feel harder than they are.
Ratios and proportions, without the confusion
How to read a ratio, simplify it, compare part-to-part and part-to-whole, and use proportions to scale recipes, maps and prices.