Temperature Converter

Convert between Fahrenheit, Celsius, and Kelvin instantly. Type any value — the other units update in real time. No rounding errors, no sign-up required.

°F
°C
K

Common Reference Points (click to load)

Reference°C°FK
Absolute zero-273.15-459.670
Water freezes032273.15
Room temperature2271.6295.15
Body temperature3798.6310.15
Water boils100212373.15

Common Temperature References

Some temperatures come up constantly in everyday life. Use the reference table in the converter above to load any of these instantly, or refer to the values below.

Body temperature

37°C / 98.6°F / 310.15 K — normal average for adults.

Water boiling point

100°C / 212°F / 373.15 K — at sea-level pressure.

Water freezing point

0°C / 32°F / 273.15 K — the basis of the Celsius scale.

Absolute zero

-273.15°C / -459.67°F / 0 K — the lowest possible temperature.

Understanding Temperature Scales

Fahrenheit is the primary temperature scale used in the United States for everyday weather, cooking, and body temperature. It was defined with 32°F as the freezing point of water and 212°F as the boiling point, giving a 180-degree span between those two fixed points.

Celsius (formerly Centigrade) is the standard in most of the world and all scientific contexts outside the US. Its two anchor points — 0°C (freezing) and 100°C (boiling) — make it intuitive for everyday use. Kelvin shares the same degree size as Celsius but starts at absolute zero (0 K = -273.15°C), making it the preferred unit in physics, chemistry, and engineering where negative temperatures are meaningless or inconvenient.

Frequently Asked Questions

How do you convert Fahrenheit to Celsius?
Subtract 32 then multiply by 5/9. Example: 98.6°F = (98.6 - 32) × 5/9 = 37°C. This formula works for all temperatures including negatives.
How do you convert Celsius to Fahrenheit?
Multiply by 9/5 then add 32. Example: 100°C = (100 × 9/5) + 32 = 212°F. Used for everyday weather, cooking, and medical temperatures in the US.
What is Kelvin and how does it relate to Celsius?
Kelvin is the SI base unit of temperature. 0 K is absolute zero — the coldest possible temperature. To convert: K = °C + 273.15. So 0°C = 273.15 K, 100°C = 373.15 K. Kelvin is used in science and physics.
What is absolute zero in Fahrenheit?
Absolute zero is 0 K = -273.15°C = -459.67°F. It is the theoretical lowest possible temperature where all molecular motion stops.
What is body temperature in Celsius?
Normal human body temperature is 37°C (98.6°F). A fever is typically above 38°C (100.4°F). These values are averages — individual normal body temperature ranges from 36.1°C to 37.2°C (97°F to 99°F).
At what temperature does water boil?
Water boils at 100°C (212°F) at standard sea-level atmospheric pressure (1 atm). At higher altitudes, water boils at lower temperatures because atmospheric pressure is lower.
Is there a temperature where Fahrenheit and Celsius are equal?
Yes — at -40°. Both scales read -40 at that exact point (-40°C = -40°F). This is because the two scales converge at that value.