What this converter does
This converter turns temperature between Celsius, Fahrenheit, Kelvin and Rankine — instantly and with the exact formulas, not rounded factors. Type a value, pick the scales, and the answer updates as you type. Unlike most converters, temperature scales have an offset as well as a ratio.
To go Celsius to Fahrenheit, multiply by 9/5 and add 32. Kelvin shares Celsius’ size but starts at absolute zero (−273.15 °C). Rankine does the same for the Fahrenheit degree. For weather, water and cooking, the °C ↔ °F pair is the one you want.
The units it covers
These scales share the same physical quantity but differ in both zero point and degree size.
View all units & their values
| Unit | Symbol | Value | Mainly used |
|---|---|---|---|
| Celsius | °C | water 0–100 | Everyday metric temperature |
| Fahrenheit | °F | water 32–212 | US everyday temperature |
| Kelvin | K | from 0 abs | SI, science, absolute zero |
| Rankine | °R | from 0 abs | US engineering, absolute °F |
The formula
Celsius to Fahrenheit scales the degree and shifts the zero point:
°F = (°C × 9⁄5) + 32 (and °C = (°F − 32) × 5⁄9)Where:
- °C = the Celsius temperature
- °F = the Fahrenheit temperature
- 9⁄5 = the degree-size ratio (1.8)
Worked example
Convert 100 °C to Fahrenheit.
100 × 9⁄5 = 180180 + 32 = 212 °FSo 100 °C is 212 °F — the boiling point of water at sea level.
The units in this example
The everyday metric temperature scale, with water freezing at 0 and boiling at 100 under standard pressure. It shares its degree size with Kelvin.
- 0 °C = 32 °F
- 37 °C = 98.6 °F
- 100 °C = 212 °F
- 0 °C = 273.15 K
The US everyday scale, with water freezing at 32 and boiling at 212. A Fahrenheit degree is 5⁄9 of a Celsius degree.
- 32 °F = 0 °C
- 98.6 °F = 37 °C
- 212 °F = 100 °C
- −40 °F = −40 °C