Which temperature scales are supported?

Five scales: Celsius (°C), Fahrenheit (°F), Kelvin (K), Rankine (°R), and Réaumur (°Ré).

What happens when I type in one field?

All other four fields update instantly as you type, so you always see all equivalents at once.

What reference points are shown in the table?

Absolute zero, water's freezing point, water's boiling point, average human body temperature, comfortable room temperature, and a moderate oven temperature — each displayed across all five scales.

Where can I learn about each scale's history?

Hover over any scale label to see a tooltip with a short historical note about the scale's inventor and origin.

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Temperature Converter

Convert temperatures between Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur instantly.

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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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