Pick a category and convert between units of length, weight, volume, or speed.
One tool, many units
Unit conversion is everyday math: recipes, travel, shipping, and schoolwork all demand switching between metric and imperial. This converter handles length, weight, volume, and speed, each with the common units people actually use.
Behind the scenes every conversion routes through a base unit, so the number is translated into meters, kilograms, liters, or meters per second, then into your target unit. The defining factors are exact, which is why one inch is precisely 2.54 centimeters and one pound is precisely 0.45359237 kilograms.
The formula
Worked example
1 kilometer equals 1,000 meters, and 1 kilogram equals about 2.205 pounds.
How to read your result
Every conversion works by translating the input into a base unit, then into the target unit. Choose the category first, then the units you want.
Frequently asked questions
- Which categories are supported?
- Length, weight, volume, and speed, with common metric and imperial units.
- Are the factors exact?
- Yes, the standard definitions are used (for example, one inch is exactly 2.54 cm).
- Need temperature?
- Use the Celsius to Fahrenheit converter, since temperature is not a simple factor.
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