Engineering tools
Unit converters and technical calculators for length, mass, energy, data, numbers, and other quantities used in design, construction, and science.
Free unit converters handle the precise translations you need in design, construction, science, and manufacturing. Length, mass, energy, pressure, speed, and temperature all convert accurately because the factors are built in and the arithmetic runs in your browser.
Common entry points are the Length Converter, Temperature Converter, Speed Converter, and Weight Converter. Switch units and the value updates immediately with full precision until you round for display.
The same engine powers area, volume, pressure, angle, frequency, power, energy, data storage, fuel economy, and time conversions. Results stay private, work on any device, and require no external service calls, so you can use them on job sites or in secure environments where uploads are not allowed.
- Length ConverterConvert length between meters, kilometers, centimeters, millimeters, miles, yards, feet, and inches instantly in your browser.
- Weight ConverterConvert weight and mass units instantly. Switch between kilograms, grams, milligrams, tonnes, pounds, ounces, and stone.
- Temperature ConverterConvert temperatures between Celsius, Fahrenheit, and Kelvin instantly. Free, accurate, and works offline in your browser.
- Volume ConverterConvert volume between liters, milliliters, cubic meters, US gallons, quarts, pints, cups, and fluid ounces instantly.
- Area ConverterConvert area between square meters, square feet, acres, hectares, square miles, and more. Fast, accurate, and free.
- Speed ConverterConvert speed between m/s, km/h, mph, knots, and feet per second. Pick from and to units, swap them, and copy the exact result.
- Data Storage ConverterConvert between bits, bytes, KB, MB, GB, TB, and PB using the binary standard where 1 KB equals 1024 bytes.
- Time Unit ConverterConvert time units instantly: milliseconds, seconds, minutes, hours, days, weeks, and years (365 days). Free, accurate, works in your browser.
- Pressure ConverterConvert pressure between pascal, kilopascal, bar, psi, and atmosphere. Fast, free, and accurate, with a swap control and live results.
- Energy ConverterConvert energy units online: joule, kilojoule, calorie, kilocalorie, watt hour, and kilowatt hour. Fast, accurate, and free.
- Power ConverterConvert power units instantly: watts, kilowatts, megawatts, and mechanical horsepower. Free, accurate, and works right in your browser.
- Angle ConverterConvert angles between degrees, radians, gradians, and turns. Fast, accurate, and free, with a swap control and copy to clipboard.
- Frequency ConverterConvert frequency between hertz, kilohertz, megahertz, and gigahertz. Fast, accurate, and free, with a swap control and copy button.
- Fuel Economy ConverterConvert fuel economy between miles per gallon (US), kilometers per liter, and liters per 100 km. Live results, swap, and copy.
- Roman Numeral ConverterConvert numbers to Roman numerals and Roman numerals back to numbers. Covers 1 to 3999, validates the range, and rejects malformed numerals.
- Number to Words ConverterConvert any whole number into English words instantly. Supports values up to the trillions, plus zero and negatives. Free and runs in your browser.