Unit converter

The Unit converter switches between US units and metric for temperature, distance, weight, volume, speed and height. It is free and pre-sets the direction for where you are.

About the Unit converter

The Unit converter is built for the conversions that come up when you travel between countries that use US units and metric. It covers temperature, distance, length, weight, volume, speed and height, with big picture buttons and one-tap common values like a 23 kg bag limit. A thermometer bar adds a plain word, from Freezing to Hot, so a forecast in a new scale makes sense right away. It suits anyone reading road signs, weather reports, recipes or baggage rules abroad.

How it works

  1. Pick a type, such as temperature or weight, with the picture buttons.
  2. Type a number, or tap a common value.
  3. Tap swap if you want to convert the other way.
  4. Read the result; for temperature, check the word on the thermometer bar.

Features

Seven kinds of unitsTemperature, distance, length, weight, volume, speed and height.
Liters and US gallonsVolume converts between liters and US gallons, handy at the gas pump.
Height in feet and inchesConverts centimeters to feet and inches in the usual way people say their height.
Big picture buttonsLarge buttons with pictures make it easy to choose the right type on a phone.
One-tap common valuesFrequent travel numbers, such as a 23 kg bag limit, are ready to tap.
Thermometer barTemperatures come with a colored bar and a word, from Freezing to Hot.
Direction pre-setStarts from US units to metric or the reverse, based on where you are. Tap swap to change it.

Why it helps on a trip

Weather makes sense. If the forecast says 30 degrees and you think in Fahrenheit, the bar tells you it is hot, not freezing.
No surprise baggage fees. Check your bag weight against a 23 kg limit in pounds before you get to the airport counter.
Read signs and speed limits. Driving abroad, convert a speed limit in km/h or a distance in miles in a second.

Tips

  • On a road trip, convert the speed limits you see most often and keep them in mind.
  • Weigh your bag at home and convert it before you fly, leaving a little room for souvenirs.
  • For a quick Celsius to Fahrenheit guess, double it and add 30; use the tool for the exact number.

Frequently asked questions

Is the Unit converter free to use?

Yes, it is free, with no account and nothing to install. It works in any phone or computer browser. It guesses your country from your device's time zone to pre-set the direction, from US units to metric or the other way, and you can tap swap to change it whenever you like.

How do I convert Celsius to Fahrenheit?

Multiply the Celsius temperature by 9, divide by 5 and add 32. For example, 20 °C is 68 °F, and 30 °C is 86 °F. A quick rough guess is to double the Celsius number and add 30. The Unit converter does the exact math and adds a word, from Freezing to Hot, so the number is easy to picture.

How many pounds is 23 kg?

23 kilograms is about 50.7 pounds. Many airlines use 23 kg, often written as 50 lb, as the weight limit for a standard checked bag in economy, but rules vary by airline and fare. The Unit converter has 23 kg as a one-tap common value, so you can check it quickly.

How many liters are in a US gallon?

One US gallon is about 3.785 liters. The UK and some other countries once used the imperial gallon, which is larger, at about 4.546 liters, so be careful with older references. The Unit converter uses US gallons for volume, which helps when comparing fuel prices or car fuel use between the US and metric countries.

How fast is 100 km/h in miles per hour?

100 kilometers per hour is about 62 miles per hour. To estimate, multiply km/h by 0.6, or divide by 1.6 to be closer. Road signs in most countries use km/h, while the United States and the United Kingdom use miles per hour. The Unit converter handles speed in both directions.

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