All Unit Converters
What Is a Unit Converter and Why Do You Need One?
A unit converter is a simple but essential tool that translates a measurement from one system of units into another. Every day, millions of people search for conversions like cm to inches, kg to lbs, or Celsius to Fahrenheit because the world runs on two competing measurement systems. The United States, Liberia and Myanmar primarily use the imperial system, with inches, feet, miles, pounds, gallons and degrees Fahrenheit. Almost every other country uses the metric system, built around meters, kilograms, liters and degrees Celsius.
This free online unit converter handles eight essential categories: length, weight, temperature, volume, area, speed, digital data and engineering pressure. Everything runs instantly in your browser. There is nothing to download, no account to create and no limit on how many conversions you can perform.
Who Uses Unit Conversions Every Day?
- Students and teachers converting between metric and imperial units for math, physics and chemistry homework.
- Cooks and bakers translating international recipes between cups, tablespoons, milliliters and grams.
- Online shoppers checking clothing sizes, screen dimensions and product weights listed in unfamiliar units.
- Travelers making sense of road signs in kilometers, weather forecasts in Celsius and fuel sold by the liter.
- Fitness enthusiasts tracking body weight in pounds or kilograms and running distances in miles or kilometers.
- Engineers, builders and DIYers working with plans and materials specified in different measurement systems.
Why Accuracy Matters
Small conversion errors can have big consequences. In 1999, NASA lost the 125 million dollar Mars Climate Orbiter because one engineering team used imperial units while another used metric. In everyday life the stakes are smaller but still real: a baking recipe with the wrong flour weight fails, a package with an underestimated weight gets surcharged, and a medication dose calculated with the wrong unit can be dangerous. This converter uses internationally standardized conversion factors and displays results with up to ten significant digits.
Frequently Asked Questions
Is this unit converter free to use?
Yes, it is completely free with no sign-up, no downloads and no usage limits.
How do I convert cm to inches?
Divide the number of centimeters by 2.54. For example, 10 cm = 3.937 inches. See the full length converter.
How do I convert kg to lbs?
Multiply kilograms by 2.20462. For example, 5 kg = 11.023 lbs. See the full weight converter.
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 and add 32. For example, 25 C = 77 F. See the full temperature converter.
Does it work offline?
Once the page has loaded, all conversions run locally in your browser, so no internet connection is required.
Is my data collected when I use the converter?
No values you type are sent to any server. All calculations happen entirely on your device.