How to use
- Type a temperature in Value. Negative numbers are fine.
- Pick the From and To scales, or tap a popular conversion.
- Read the answer. The exact formula for your pair is shown under it.
Formula
The scales differ by an offset as well as a size, so each pair has its own formula:
°F = °C × 1.8 + 32
°C = (°F − 32) ÷ 1.8
K = °C + 273.15
°R = °F + 459.67
These equations are exact. Absolute zero, the coldest possible temperature, is 0 K = −273.15 °C = −459.67 °F. The converter won’t go below it.
Examples
- 20 °C to °F: 20 × 1.8 + 32 = 68 °F
- 350 °F to °C: (350 − 32) ÷ 1.8 = 176.67 °C
- 37 °C to °F: 37 × 1.8 + 32 = 98.6 °F
- −40 °C to °F: −40 °F, the one reading where both scales match
Conversion charts
| Celsius | Fahrenheit |
|---|---|
| −20 °C | −4 °F |
| −10 °C | 14 °F |
| 0 °C | 32 °F |
| 10 °C | 50 °F |
| 20 °C | 68 °F |
| 25 °C | 77 °F |
| 30 °C | 86 °F |
| 35 °C | 95 °F |
| 40 °C | 104 °F |
Oven temperatures
| Fahrenheit | Celsius (exact) | Gas mark |
|---|---|---|
| 300 °F | 148.9 °C | 2 |
| 325 °F | 162.8 °C | 3 |
| 350 °F | 176.7 °C | 4 |
| 375 °F | 190.6 °C | 5 |
| 400 °F | 204.4 °C | 6 |
| 425 °F | 218.3 °C | 7 |
| 450 °F | 232.2 °C | 8 |
Recipes round these to steps such as 180 °C for 350 °F. Gas marks follow the Which? chart; they aren’t standardised, so other charts differ slightly.
Body temperatures
| Celsius | Fahrenheit |
|---|---|
| 36 °C | 96.8 °F |
| 36.5 °C | 97.7 °F |
| 37 °C | 98.6 °F |
| 37.5 °C | 99.5 °F |
| 38 °C | 100.4 °F |
| 39 °C | 102.2 °F |
| 40 °C | 104 °F |
The NHS treats 38 °C or above as a high temperature.
More detail: differences, kelvin and Rankine
- Temperature changes convert by 1.8 only, with no +32. A rise of 10 °C is a rise of 18 °F.
- Kelvin has no degree sign: write 300 K, not 300 °K. A change of 1 K equals a change of 1 °C.
- Rankine (°R) is an absolute scale with Fahrenheit-sized degrees. It is used in some US engineering work.
Measuring the ingredients too? Try the volume converter.