Temperature Converter
Convert temperatures between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur instantly.
About this tool
Enter a value in any of the five temperature scales — Celsius, Fahrenheit, Kelvin, Rankine, or Réaumur — and all others update instantly. A reference table shows key temperatures (absolute zero, freezing, boiling, body, room, and oven) across all five scales. Hover over any scale name to read a short historical note about its inventor. The formula panel displays the exact conversion formula from the scale you last edited.
How to use
- 1 Type a temperature value into any of the five input fields.
- 2 All other scales update immediately — no button click required.
- 3 Check the Formula panel below the inputs to see the exact conversion formula for the scale you entered.
- 4 Scroll down to the Reference Points table to compare well-known temperatures across all five scales at a glance.
Frequently Asked Questions
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