Temperature Converter
Convert between Celsius, Fahrenheit, and Kelvin
Water freezes at 0°C and boils at 100°C
Water freezes at 32°F and boils at 212°F
Absolute zero is 0 K (-273.15°C)
Quick Reference
Water Freezes
0°C = 32°F = 273K
Room Temp
20°C = 68°F = 293K
Water Boils
100°C = 212°F = 373K
Temperature Scales Explained
Conversion Formulas
°F = (°C × 9/5) + 32
°C = (°F - 32) × 5/9
K = °C + 273.15
History
Celsius: Developed by Anders Celsius in 1742, based on water's freezing (0°) and boiling (100°) points.
Fahrenheit: Created by Daniel Fahrenheit in 1724. Originally based on brine freezing point and human body temperature.
Kelvin: Proposed by William Thomson (Lord Kelvin) in 1848. Starts at absolute zero, the coldest possible temperature.
FAQ
Why does the US use Fahrenheit?
Historical reasons. The US adopted Fahrenheit before the metric system became standard. Most other countries use Celsius.
What is absolute zero?
Absolute zero (0 K or -273.15°C) is the lowest possible temperature where molecular motion stops completely.
Which scale is most accurate?
All three scales are equally accurate. Kelvin is preferred in science because it starts at absolute zero.