Temperature Converter
Convert temperature readings. These are readings, not differences: a change of 1 K equals a change of 1 °C or 1.8 °F. Exact factors, a quick reference table and worked examples.
100 °C = 212 °F
The same value in every unit
| Unit | Symbol | Value |
|---|---|---|
| Celsius | °C | 100 |
| Kelvin | K | 373.15 |
| Fahrenheit | °F | 212 |
| Rankine | °R | 671.67 |
How to convert temperature units
Temperature scales differ by an offset as well as by the size of the degree, so a reading cannot be converted by a factor alone. Convert to a common point first, then to the scale you want.
°F = °C × 9 ÷ 5 + 32 K = °C + 273.15 °R = °F + 459.67
A difference of 1 K is the same as 1 °C, and 1.8 °F or 1.8 °R: only readings need the offset.
Quick reference table
Familiar temperatures in every scale.
| Reading | °C | K | °F | °R |
|---|---|---|---|---|
| Absolute zero | -273.15 | 0 | -459.67 | 0 |
| Liquid nitrogen boils | -195.79 | 77.36 | -320.422 | 139.248 |
| Water freezes | 0 | 273.15 | 32 | 491.67 |
| Room temperature | 20 | 293.15 | 68 | 527.67 |
| Human body | 37 | 310.15 | 98.6 | 558.27 |
| Water boils (1 atm) | 100 | 373.15 | 212 | 671.67 |
| Soldering iron, typical | 350 | 623.15 | 662 | 1 121.67 |
| Steel melts (about) | 1 500 | 1 773.15 | 2 732 | 3 191.67 |
Common values: °C to °F
| Celsius (°C) | Fahrenheit (°F) |
|---|---|
| -40 °C | -40 °F |
| 0 °C | 32 °F |
| 20 °C | 68 °F |
| 25 °C | 77 °F |
| 37 °C | 98.6 °F |
| 100 °C | 212 °F |
| 150 °C | 302 °F |
| 200 °C | 392 °F |
| 500 °C | 932 °F |
| 1 000 °C | 1 832 °F |
Worked examples
Convert 100 °C to °F
- °F = °C × 9 ÷ 5 + 32
- 100 × 9 ÷ 5 + 32 = 212 °F
Convert 98.6 °F to °C
- °C = (°F − 32) × 5 ÷ 9
- (98.6 − 32) × 5 ÷ 9 = 37 °C
Convert 25 °C to kelvin
- K = °C + 273.15
- 25 + 273.15 = 298.15 K
The units explained
| Unit | Symbol | Scale | Where it is used |
|---|---|---|---|
| Celsius | °C | — | — |
| Kelvin | K | — | — |
| Fahrenheit | °F | — | — |
| Rankine | °R | — | — |
Key facts
- °F = °C × 9 ÷ 5 + 32. K = °C + 273.15.
- Water freezes at 0 °C (32 °F) and boils at 100 °C (212 °F) at standard pressure.
- Absolute zero is 0 K = −273.15 °C = −459.67 °F.
Related converters, guides and tools
- Other converters: Pressure converter, Density converter, Angles converter, Flow Rate converter, Time converter, Stress converter, Strain converter, Velocity converter, Volume converter, Length converter, Mass converter, Force converter, Torque converter, Power converter, Energy converter.
- Guides: Sensors.
- Unit Conversions: every converter on one tabbed page that remembers the tabs you use.
- My Dashboard (members): put this converter on your own workspace as a widget beside the others.
FAQ
How do I convert Celsius to Fahrenheit?
Multiply by 9, divide by 5 and add 32: °F = °C × 9 ÷ 5 + 32. For example 20 °C is 68 °F.
How do I convert Fahrenheit to Celsius?
Subtract 32 and multiply by 5 ÷ 9: °C = (°F − 32) × 5 ÷ 9. For example 212 °F is 100 °C.
What is absolute zero?
0 K, which is −273.15 °C or −459.67 °F: the temperature at which a perfect gas would have no thermal energy.
Are the conversion factors exact?
Where a unit is defined exactly (the inch is 25.4 mm, the pound is 0.45359237 kg, standard gravity is 9.80665 m/s²) the factor is exact; others are given to ten or more digits. Results are shown to seven significant digits.
References
- NIST Special Publication 811, Guide for the Use of the International System of Units (SI), and NIST Handbook 44, Appendix C (general tables of units of measurement).
- BIPM, The International System of Units (SI Brochure), 9th edition; ISO 80000 (quantities and units).
Last reviewed: November 2026.