Unit Converter

What this tool does

Convert a length, a weight, or a temperature from one unit to another. Use it for a recipe, a shipment, or a weather reading when you already know the number and only need the other unit. Currency, area, and volume are not on this page, and a temperature below absolute zero is rejected.

How to use

1. Choose a category: length, weight/mass or temperature.
2. Enter a value and choose the from and to units.
3. The result updates as you type. Use Swap units to reverse the conversion.

Examples

• Length

  1 meter = 100 centimeters = about 3.28084 feet.

• Temperature

  0°C = 32°F = 273.15 K.

How it works

Length and weight conversions multiply through a base unit (meter or kilogram). Temperature conversions are not simple multiples: they use the Celsius/Fahrenheit/Kelvin formulas and reject values below absolute zero.

Limitations

Length, weight, and temperature are the only conversions on this page. It does not convert currency, area, or volume. Temperature below absolute zero is rejected. Length and mass use fixed factors, so the result can show more decimal places than a measuring tool would.

See the disclaimer for what these tools do not cover.

FAQ

Is the Unit Converter free?

Yes. You can convert length, weight, and temperature here without paying or creating an account.

Are these exact conversions?

Length and mass use international standard factors, such as 1 inch = 2.54 centimeters exactly. Temperature uses the standard formulas.

Is my input sent to a server?

No. The value and units you choose are converted in this browser tab. Tools Star Hub does not send that value to a server or save it in local storage.

How do I convert Celsius to Fahrenheit?

Multiply the Celsius value by 9/5 and add 32. For example, 20 °C is 20 × 9 ÷ 5 + 32 = 68 °F.

How many centimeters are in an inch?

One inch is exactly 2.54 centimeters, so 12 inches (one foot) is 30.48 centimeters.

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