°C
Celsius
Water freezes at 0°C, boils at 100°C
°C
°F
Fahrenheit
Water freezes at 32°F, boils at 212°F
°F
K
Kelvin
Absolute zero = 0 K
K
°R
Rankine
Absolute zero = 0°R (°F + 459.67)
°R
Common Reference Points — click to load
Frequently Asked Questions
Multiply the Celsius value by 9/5 (1.8), then add 32. Example: 100°C → 100 × 1.8 + 32 = 212°F. To go the other way: subtract 32 then multiply by 5/9.
Absolute zero (0 K = −273.15°C = −459.67°F) is the theoretical minimum temperature where all molecular thermal motion stops. It is physically impossible to cool anything to exactly absolute zero.
Fahrenheit is used primarily in the United States, Belize, the Bahamas, and the Cayman Islands. Most other countries use Celsius (°C), while Kelvin is the SI unit used in scientific contexts worldwide.