Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin.
Click any scale to type in it. Click a result to use it as input.
Frequently Asked Questions
How do I convert Celsius to Fahrenheit?
Formula: °F = (°C × 9/5) + 32. Key reference points: 0°C = 32°F (freezing), 20°C = 68°F (room temp), 37°C = 98.6°F (body temp), 100°C = 212°F (boiling). Quick mental estimate: double the Celsius and add 30 (works well between 0–30°C).
How do I convert Fahrenheit to Celsius?
Formula: °C = (°F − 32) × 5/9. Example: 98.6°F body temperature = (98.6 − 32) × 5/9 = 66.6 × 0.556 = 37°C. For oven temperatures: 350°F = 177°C, 400°F = 204°C, 450°F = 232°C.
What is absolute zero in Celsius and Fahrenheit?
Absolute zero (0 Kelvin) is the coldest possible temperature: −273.15°C or −459.67°F. At absolute zero, all molecular motion ceases. It is a theoretical limit — no physical object has ever reached exactly 0 K, though scientists have gotten within billionths of a degree.
When is Kelvin used instead of Celsius or Fahrenheit?
Kelvin is the SI base unit for temperature, used in science, physics, and engineering where absolute temperature matters. It has no negative values, making equations simpler. Examples: gas laws (PV = nRT), blackbody radiation, and astrophysics (star temperatures are in thousands to millions of Kelvin).