🔁 Unit Converters
Inches, pounds, Fahrenheit and more, instant US-first conversions.
Length Converter
Convert inches, feet, yards and miles to centimeters, meters and more, all at once.
Weight Converter
Convert pounds and ounces to kilograms and grams, with stones and tonnes too.
Speed Converter
Convert mph to km/h and back, plus meters per second, knots and feet per second.
Volume Converter
Convert cups, fluid ounces, tablespoons and gallons to milliliters and liters.
Temperature Converter
Convert Fahrenheit, Celsius and Kelvin instantly, all three at once.
Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals to numbers, both ways.
Shoe Size Converter
Convert US, UK and EU shoe sizes for men, women and kids with a size chart.
Number Base Converter
Convert between binary, decimal, hexadecimal and octal at once.
About these unit converters
US units first, metric alongside. Enter one value and every unit fills in at once, so inches to centimeters, pounds to kilograms, Fahrenheit to Celsius and cups to milliliters are all answered in a single view without switching tools.
The conversion factors are the exact official definitions, not rounded approximations, and you can tap any result to copy it. The shoe size and Roman numeral converters round out the set for the questions a plain unit table cannot answer.