Converters
Metric & imperial units, time zones
Calculators
Time Zone Converter
Free time zone converter: find the current time in any city or time zone instantly, with world clock support and live clock comparisons.
Amps to Watts Calculator
Free amps to watts calculator: convert electrical current (amps) and voltage into power in watts, kilowatts and kWh. Fast for any appliance or circuit.
Unit converters
Length Converter
Convert between metric and imperial length units — millimeters, centimeters, meters, kilometers, inches, feet, yards, miles and nautical miles.
Weight & Mass Converter
Convert between metric and imperial weight and mass units — milligrams, grams, kilograms, tonnes, ounces, pounds and stones.
Temperature Converter
Convert between Celsius, Fahrenheit and Kelvin. Temperature is an affine scale, so conversions use both a multiplier and an offset.
Area Converter
Convert between metric and imperial area units — square meters, square kilometers, hectares, acres, square feet, square yards and more.
Volume Converter
Convert between metric and imperial volume units — milliliters, liters, cubic meters, gallons, quarts, pints, fluid ounces and cups.
Speed Converter
Convert between speed units — meters per second, kilometers per hour, miles per hour, knots and feet per second. Free instant converter.
Data Storage Converter
Convert between digital storage units — bits, bytes, kilobytes, megabytes, gigabytes, terabytes and petabytes. Uses binary (1,024) multiples.
Time Converter
Convert between time units — milliseconds, seconds, minutes, hours, days, weeks, months (average) and years (average). Free instant converter.
Power Converter
Convert between power units — milliwatts, watts, kilowatts, megawatts, horsepower, metric horsepower and BTU per hour. Free instant converter.
Energy Converter
Convert between energy units — joules, kilojoules, megajoules, calories, kilocalories, watt-hours, kilowatt-hours and BTU.
Pressure Converter
Convert between pressure units — pascals, kilopascals, megapascals, bar, millibar, atmospheres, psi, mmHg and inches of mercury.