Free Online Unit Converters: Length, Weight, Temperature & More

Need to quickly convert meters to feet, kilograms to pounds, or Celsius to Fahrenheit? Instead of searching for formulas or downloading apps, you can use our free online unit converters to get instant, accurate results right in your browser. All conversions run client-side - nothing is sent to a server.

6 Free Unit Converters

We offer six dedicated converters, each with bidirectional input, a swap button, and an "all conversions" table so you can see every unit at a glance:

• Length Converter - micrometers, millimeters, centimeters, meters, kilometers, inches, feet, yards, miles, and nautical miles
• Weight Converter - micrograms, milligrams, grams, kilograms, tonnes, ounces, pounds, stone, short tons, and long tons
• Temperature Converter - Celsius, Fahrenheit, Kelvin, and Rankine
• Area Converter - square millimeters to square miles, hectares, acres, and everything in between
• Volume Converter - milliliters, liters, cubic meters, teaspoons, tablespoons, cups, pints, quarts, and gallons
• Speed Converter - m/s, km/h, mph, knots, ft/s, and Mach

How to Use the Converters

1. Open any converter page listed above
2. Enter a value in the "From" field and pick the source unit
3. The "To" field updates instantly - pick a different target unit anytime
4. Use the swap button to reverse the conversion direction
5. Scroll down to see the value expressed in every available unit at once

Common Conversions People Search For

Here are some of the most frequently searched unit conversions you can do instantly:

• 1 mile = 1.60934 kilometers - handy for travelers and runners
• 1 kg = 2.20462 pounds - essential for cooking, fitness, and shipping
• 100°C = 212°F - boiling point of water, a classic reference
• 1 acre = 4,046.86 m² - useful for real estate and agriculture
• 1 gallon = 3.78541 liters - important for US-to-metric cooking
• 100 km/h = 62.14 mph - the speed limit conversion every driver needs

Why Use an Online Converter?

• Instant results - no page reloads, results update as you type
• 100% private - all math runs in your browser, nothing is uploaded
• No sign-up or downloads - just open the page and start converting
• Mobile friendly - works perfectly on phones and tablets
• Bidirectional - type in either field and the other updates automatically

Temperature Conversion Formulas

Unlike other unit conversions that use simple multiplication, temperature conversions require addition and subtraction:

• °C to °F: multiply by 9/5, then add 32
• °F to °C: subtract 32, then multiply by 5/9
• °C to K: add 273.15
• K to °C: subtract 273.15

Our temperature converter handles all of this automatically, including the less common Rankine scale used in some engineering fields.

Bookmark any converter you use regularly - they load instantly and work offline once cached. No ads, no popups, just fast, accurate conversions.