All-in-One Temperature Converter
Type a temperature in any scale and instantly see it in all eight: Celsius, Fahrenheit, Kelvin, Rankine, Réaumur, Delisle, Newton and Rømer.
How to use the All-in-One Temperature Converter
- Enter the temperature.
- Choose the scale it is in.
- Read the value in every other scale.
How it works
Every scale is converted through kelvin, the SI base unit. Celsius and Kelvin share the same degree size, as do Fahrenheit and Rankine; Réaumur, Newton and Rømer are historical scales defined by different fixed points, and Delisle counts downwards from the boiling point of water, so its numbers fall as temperature rises.
Fixed points on all eight scales
| Point | °C | °F | K | °R | °Ré | °De | °N | °Rø |
|---|---|---|---|---|---|---|---|---|
| Absolute zero | -273.15 | -459.67 | 0 | 0 | -218.52 | 559.73 | -90.14 | -135.9 |
| Water freezes | 0 | 32 | 273.15 | 491.67 | 0 | 150 | 0 | 7.5 |
| Body temperature | 37 | 98.6 | 310.15 | 558.27 | 29.6 | 94.5 | 12.21 | 26.93 |
| Water boils | 100 | 212 | 373.15 | 671.67 | 80 | 0 | 33 | 60 |
Frequently asked questions
How many temperature scales are there?
Eight are in common reference use: Celsius, Fahrenheit, Kelvin, Rankine, Réaumur, Delisle, Newton and Rømer. Only the first three are used widely today.
Which scale has no negative numbers?
Kelvin and Rankine start at absolute zero, so they are never negative.
Why does Delisle go backwards?
Joseph-Nicolas Delisle set 0 at the boiling point of water and counted upwards as it got colder.
At what temperature are Celsius and Fahrenheit equal?
−40°.