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Converters

Convert between Celsius, Fahrenheit and Kelvin

Temperature converter takes a reading, the scale it is on, and shows the same temperature in Celsius, Fahrenheit and Kelvin. Developers use it when sensor logs report one scale and a ticket, test or UI uses another. Choose the starting scale in "From" (Celsius by default), type the number, and read all three lines: Fahrenheit is C times 9/5 plus 32, Kelvin is C plus 273.15. A reading below absolute zero is rejected with a message instead of being converted.

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How to use Temp Converter

  1. Open Temp Converter in the Toolbox101 app.
  2. Pick the scale your number is on with From: Celsius, Fahrenheit or Kelvin.
  3. Type the temperature into the Temperature box, for example 98.6.
  4. Read the three scales in the Output box.
  5. Click Copy to keep the converted temperatures for your report, test or chart.

Worked example

Temp Converter returns the output below for this combination.

Settings

From: Fahrenheit

Input

98.6

Output

Celsius: 37 °C
Fahrenheit: 98.6 °F
Kelvin: 310.15 K

Check it yourself: open Temp Converter and enter the same settings and input.

Frequently asked questions

Does it convert Fahrenheit to Celsius?

Yes, in every direction. Set From to Fahrenheit, enter 98.6, and the Celsius line reads 37 and the Kelvin line 310.15. Starting from Kelvin or Celsius works the same way, and all three scales are always listed.

What does it do with a temperature below absolute zero?

It refuses: anything below 0 K, -273.15 °C or -459.67 °F gets a message that the value is below absolute zero, instead of a number that cannot exist.

What should I type for common reference points?

Freezing water is 0 °C, 32 °F, 273.15 K. Boiling water at sea level is 100 °C, 212 °F, 373.15 K. A room at 22 °C is 71.6 °F, 295.15 K. These anchors let you sanity-check any conversion in seconds.

How many decimals does it show?

Up to ten significant digits with trailing zeros removed, so 21 °C reads 69.8 °F and 294.15 K rather than 69.80 and 294.150000.

Use Temp Converter now

Open Temp Converter in the app

Runs in your browser. Nothing you type is uploaded.