Temperature Converter

Temperature Converter converts between degrees Celsius, degrees Fahrenheit and kelvins, exactly. Unlike length or weight, temperature scales do not just differ by a factor: their zeros are in different places, so a conversion needs an offset as well as a multiplication, and doubling a temperature in °C does not double it in °F. The converter does both steps in decimal arithmetic, so 98.6 °F comes out as exactly 37 °C, and it refuses anything colder than absolute zero (0 K, −273.15 °C, −459.67 °F), the lowest temperature there can be. It is useful for body temperatures and fevers, oven settings in recipes from other countries, weather forecasts, and science homework that needs kelvins.

1. Type the temperature; minus signs are fine.
2. Choose the scale it is in and the one you want, or press a common conversion.
3. Read the answer and the other scale in the table.

• This converts temperatures, not temperature differences. A rise of 10 °C is a rise of 18 °F, not 50 °F.
• The Rankine and Réaumur scales are not included.
• Oven gas marks are not included: they are a dial scale whose temperatures are only approximate, and charts of them disagree by several degrees.
• Values below absolute zero are refused rather than converted.
• The conversion runs in your browser and nothing is sent.

98.6 °F, the textbook normal body temperature. A fever is usually counted from about 38 °C, which is 100.4 °F.

Subtract 30 and halve it for a rough answer: 80 °F is about 25 °C (exactly 26.7 °C). For exact values use (°F − 32) × 5/9.

At −40: −40 °C is −40 °F.

Kelvin is an absolute scale starting at absolute zero, and since 1967 it has been written simply as K: 300 K, not 300 °K.