Temperature Converter
Convert Celsius, Fahrenheit and kelvin — body temperature, oven settings, weather and lab values — with the exact formulas shown. Results update as you type; exact factors shown.
One degree Fahrenheit is -17.2222 degrees Celsius — see the exact factor, not a rounded rule of thumb.
How the temperature converter works
Celsius and Fahrenheit are offset scales, so the conversion is not a simple multiplication: °F = °C × 9/5 + 32 and °C = (°F − 32) × 5/9. Kelvin has the same size of degree as Celsius but starts at absolute zero: K = °C + 273.15. The two scales meet at −40°.
The US uses customary units (US gallon, short ton, °F) in daily life; NIST SP 811 gives the exact SI factors.
Common temperature conversions
| From | To | Units |
|---|---|---|
| 0 °C | 32 °F | degrees Celsius to degrees Fahrenheit |
| 100 °C | 212 °F | degrees Celsius to degrees Fahrenheit |
| 37 °C | 98.6 °F | degrees Celsius to degrees Fahrenheit |
| -40 °C | -40 °F | degrees Celsius to degrees Fahrenheit |
| 20 °C | 68 °F | degrees Celsius to degrees Fahrenheit |
| 32 °F | 0 °C | degrees Fahrenheit to degrees Celsius |
| 98.6 °F | 37 °C | degrees Fahrenheit to degrees Celsius |
| 212 °F | 100 °C | degrees Fahrenheit to degrees Celsius |
| 350 °F | 176.6667 °C | degrees Fahrenheit to degrees Celsius |
| 0 K | -273.15 °C | kelvins to degrees Celsius |
Units in this converter and their exact factors
| Unit | Symbol | To kelvin |
|---|---|---|
| degree Celsius | °C | x+273.15 |
| degree Fahrenheit | °F | (x-32)×5÷9+273.15 |
| kelvin | K | x |
FAQFrequently asked questions about temperature conversion
What is the formula to convert Celsius to Fahrenheit?
Multiply by 9/5 (1.8) and add 32. So 20 °C = 20 × 1.8 + 32 = 68 °F.
What is normal body temperature in Fahrenheit?
About 98.6 °F, which is 37 °C. Many modern references quote a slightly lower average of around 36.6–36.8 °C.
At what temperature are Celsius and Fahrenheit equal?
At −40 degrees: −40 °C is exactly −40 °F.
What is absolute zero?
0 K, which is −273.15 °C or −459.67 °F — the lowest possible temperature.
What is 180 °C in Fahrenheit for baking?
356 °F; most recipes round it to 350 °F. Fan-forced ovens are usually set about 20 °C lower.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Institute of Standards and Technology (NIST) — United States's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.