Convert between commonly used units across five categories — Length, Temperature, Area, Volume, and Weight. Select a category, choose your units, enter a value, and get an instant result.
How to use this calculator
Select a category tab (Length, Temperature, Area, Volume, or Weight). Enter a value, choose your From and To units, and the result updates instantly. Use the ⇄ Swap button to reverse the conversion direction. Clear resets inputs to defaults while keeping the last result visible.
Convert between metric and imperial length units — meters, feet, miles, and more.
1 Meter
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Foot
Results update automatically as you change values or units. Use the Swap button to reverse the conversion direction.
About Unit Conversion
A unit of measurement is a defined magnitude of a quantity used as a standard for measurement. Different countries and disciplines use different systems — primarily the International System of Units (SI) and the US customary / Imperial system. This calculator covers the most commonly used conversions across five categories, enabling quick and accurate conversions for everyday tasks, science, cooking, engineering, and more.
Category Overview
| Category | Units Available | Base Unit |
|---|---|---|
| Length | Meter, Kilometer, Mile, Foot, Inch, Yard, Light Year… | Meter |
| Temperature | Celsius, Fahrenheit, Kelvin | Celsius |
| Area | Square Meter, Acre, Hectare, Square Mile, Square Foot… | Square Meter |
| Volume | Liter, Gallon (US/Imperial), Cubic Meter, Fluid Ounce… | Cubic Meter |
| Weight | Kilogram, Pound, Ounce, Metric Ton, Long Ton… | Kilogram |
Unit conversion is one of the most fundamental and frequently needed calculations in everyday life. Whether you are cooking from a recipe that uses metric measurements, calculating fuel efficiency for a road trip, or understanding a weather forecast in a foreign country, the ability to quickly convert between units of measurement is an essential skill. Errors in unit conversion have caused real-world disasters, including the loss of the Mars Climate Orbiter in 1999 due to a mix-up between metric and imperial units.
The world primarily uses two measurement systems: the International System of Units (SI), commonly known as the metric system, and the United States Customary System (USCS), which is derived from the older British Imperial system. The metric system is used by virtually every country in the world for science, medicine, and most everyday purposes. The United States is one of only three countries — along with Myanmar and Liberia — that have not officially adopted the metric system as their primary system of measurement.
The most common length conversion is between feet/inches and meters/centimeters. One inch equals exactly 2.54 centimeters, which means one foot equals 30.48 cm and one meter equals approximately 3.281 feet. For longer distances, one mile equals 1.609 kilometers, which is why a 5K race is approximately 3.1 miles.
One kilogram equals 2.20462 pounds. A person who weighs 70 kg weighs approximately 154 lbs. One pound equals 16 ounces, and one stone (used in the UK) equals 14 pounds or approximately 6.35 kg. For cooking, one ounce equals 28.35 grams.
Temperature conversion between Celsius and Fahrenheit uses the formula: F = (C x 9/5) + 32. To convert back: C = (F - 32) x 5/9. Some useful reference points: water freezes at 0°C (32°F), body temperature is 37°C (98.6°F), and water boils at 100°C (212°F) at sea level.
When converting units, always double-check the direction of the conversion. A common mistake is multiplying when you should divide, or vice versa. For critical applications such as medication dosing or engineering calculations, always verify your result using a second method or calculator. Our unit conversion calculator supports length, weight, temperature, area, and volume conversions with high precision.
Frequently Asked Questions