Conversion Tools

Free weight converter. Convert between grams, kilograms, ounces, pounds, stone and tons with exact factors, and see the answer in every unit at once.

Free volume converter. Convert between liters, milliliters, cubic meters, US gallons, quarts and cups, and see the answer in every unit at once.

Free time converter. Convert between milliseconds, seconds, minutes, hours, days, weeks and years, and see the exact answer for any amount of time.

Free temperature converter. Convert between Celsius, Fahrenheit and Kelvin with the exact formulas, for weather, cooking, fever readings and science.

Free speed converter. Convert mph, km/h, knots, m/s, feet per second, Mach and running pace with exact factors, and see the speed in every unit at once.

Free length converter. Convert between meters, kilometers, centimeters, millimeters, miles, yards, feet and inches with exact factors for any distance.

Free energy converter. Convert between joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours and BTU for food, electricity and heating.

Free digital data storage converter. Convert bits, bytes, KB, MB, GB, TB and PB, in decimal (1000) or binary (1024) units, and see the answer in every unit.

Free area converter. Convert between square meters, square feet, square yards, acres, hectares, square kilometers and square centimeters for any size.

Free speed calculator. Find speed from distance and time, or distance or time from the other two, in km, miles or knots, with pace and a distance-time graph.

Free shoe size calculator. Convert US men's and women's sizes to EU and UK, find the foot length for a size, or find your size from a foot measurement.

Free Roman numeral converter. Change numbers from 1 to 3999 into Roman numerals, read Roman numerals as numbers, or write a date in Roman numerals.

Free height calculator. Change a height between feet and inches and centimeters, and meters, and see how it compares with a door, a counter and a hoop.

Free unit converter. Convert length, weight, temperature, area, volume and time between metric and US units with exact factors, and see all the units at once.

Free Base64 encoder and decoder. Change text to Base64 and back, with Unicode and emoji support, URL-safe Base64, and a copy button. Works in your browser.