Unit Converter

Length, weight & temperature. Answers appear as you type — fast, free, no sign-up.

Convert length, weight, and temperature without hunting through search results. This free unit converter handles everyday swaps — miles to kilometers, pounds to kilograms, Fahrenheit to Celsius — plus cooking and science units, with answers appearing as you type. No sign-up, and it works on any device.

8.04672 km
5 mi = 8.04672 km

How to use

  1. Choose a category: length, weight, or temperature.
  2. Enter a value and pick the “from” and “to” units.
  3. The converted result appears instantly — flip the units with one tap.
  4. Use it for recipes, travel, homework, or DIY measurements.

Frequently asked questions

How does the mile to kilometer conversion work?

One mile is defined as exactly 1,609.344 meters, and one kilometer is exactly 1,000 meters. So to convert, multiply by 1,609.344 to get meters, then divide by 1,000 to get kilometers. Example: 5 mi → 5 × 1,609.344 ÷ 1,000 = 8.04672 km (≈ 8.047 km).

Why can't temperature use the same multiply formula?

Length and weight units measure from the same zero, so you only rescale them. Temperature scales start at different zeros, so there's an offset too. Convert to °C first, then out: °C = (°F − 32) × 5/9 and °C = K − 273.15; going the other way: °F = °C × 9/5 + 32 and K = °C + 273.15.

What's the difference between pounds and kilograms?

They measure the same thing — mass — in different systems: kilograms are the SI (metric) unit, pounds are imperial/US customary. One kilogram equals exactly 2.20462 pounds. So a 70 kg person weighs about 154 lb; pound numbers read bigger than kilogram numbers for the same mass.

Is this converter free? Does my data leave my device?

Yes — completely free, no account, no sign-up. Every conversion is calculated in your browser with plain JavaScript; nothing you type is sent anywhere. It works on phones, tablets, and desktops.

How do I convert square feet to square meters?

Multiply square feet by 0.092903. A 1,000 sq ft apartment is about 92.9 m². Going the other way, multiply square meters by 10.764 to get square feet.

How many ounces are in a gallon?

A US gallon holds 128 US fluid ounces — that’s 8 pints or 16 cups. Note the UK (imperial) gallon is bigger at 160 fluid ounces, which matters when following British recipes.

What is the Celsius to Fahrenheit formula?

Multiply Celsius by 9/5 (1.8) and add 32. So 20°C × 1.8 + 32 = 68°F. To go back: subtract 32, then multiply by 5/9.