Numbers & units
- Binary / hex / decimal converterConvert a number between binary, octal, decimal and hexadecimal.
- Length converterMeters, km, miles, feet, inches and more.
- Pounds to kg converterConvert weight between kg, g, lb, oz and more.
- km/h to mph converterConvert speed between km/h, m/s, mph and knots.
- MB to GB converterConvert data size between bytes, KB, MB, GB, TB.
- Area converterSquare meters, hectares, acres, square feet and more.
- Celsius to Fahrenheit converterConvert temperature between Celsius, Fahrenheit and Kelvin.
- Unix timestamp to date converterConvert a Unix timestamp to a readable date and back.
- Number to words converterSpell out a number in full words.
- Percentage calculatorX% of Y, and percentage change between two values.
- Roman numerals converterConvert a number to Roman numerals and back.
- Rule of three (cross multiplication)Find the 4th value of a proportion: if A is to B, then C is to what?
- Weighted average (grades with coefficients)Compute a weighted average. One line per grade: grade weight.
- Statistics: median, mode, variance, standard deviationPaste a series of numbers: mean, median, mode, range, variance and standard deviation.
- Fraction calculatorAdd, subtract, multiply and divide two fractions, with a simplified result.
- Online scientific calculatorTrigonometry, logarithms, powers, factorial, degrees or radians, history.
- Function plotter (curves and intersections)Plot up to three functions of x, zoom, pan, find zeros and intersections.
- Printable multiplication tablesTables from 1 to 30, PDF printing and a quick quiz.
- Volume converterLiters, milliliters, gallons, cups, spoons, fluid ounces.
- Time unit converterSeconds, minutes, hours, days, weeks, months, years.
- Pressure converterPascal, bar, psi, atmosphere, mmHg.
- Energy converterJoules, calories, kilowatt-hours, BTU.
- Power converterWatts, kilowatts, metric horsepower and mechanical horsepower.
- Angle converterDegrees, radians, gradians, turns.
- Fuel consumption converterL/100 km, km/L, miles per gallon (US and UK).
- Mean, median, standard deviationCompute the mean, median, mode, sum, min, max and standard deviation of a list of numbers.
- GCD and LCM calculatorGreatest common divisor and least common multiple of several integers.
- Prime checker and factorizationCheck whether a number is prime and get its prime factorization.
- Decimal to fractionConvert a decimal number into a simplified fraction.
- Scientific notation converterWrite a number in scientific and engineering notation.
- Percentage change calculatorCompute the percentage increase or decrease between two values.
- Quadratic equation solverSolve ax² + bx + c = 0 (discriminant and real or complex roots).