Temperature Converter: Celsius, Fahrenheit, and Kelvin
Convert any temperature between °C, °F, and K instantly. All three values update at once with the exact formula shown.
This temperature converter shows Celsius, Fahrenheit, and Kelvin simultaneously. Type a value in any field and the other two update instantly with the exact formula used. Useful for weather comparisons between countries that use different scales, converting recipe oven temperatures, reading scientific data in Kelvin, or checking medical temperature references. The converter validates against absolute zero so it catches inputs that are physically impossible.
Frequently asked questions
How do you convert Celsius to Fahrenheit?
Multiply the Celsius temperature by 9/5 (or 1.8) and add 32. The formula is °F = (°C × 9/5) + 32. For example, 100°C equals (100 × 1.8) + 32 = 212°F.
How do you convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit temperature, then multiply by 5/9. The formula is °C = (°F − 32) × 5/9. For example, 98.6°F equals (98.6 − 32) × 5/9 = 37°C.
What temperature is the same in Celsius and Fahrenheit?
-40 degrees is the only point where Celsius and Fahrenheit show the same number. At −40°C = −40°F, the two scales intersect.
What is 37 degrees Celsius in Fahrenheit?
37°C equals 98.6°F. This is normal human body temperature. Using the formula: (37 × 9/5) + 32 = 66.6 + 32 = 98.6°F.
What is Kelvin and how is it different from Celsius?
Kelvin is an absolute temperature scale that starts at absolute zero (0 K), the coldest possible temperature. One Kelvin degree is the same size as one Celsius degree, but Kelvin has no negative values. To convert Celsius to Kelvin, add 273.15. Water freezes at 273.15 K and boils at 373.15 K.
What is absolute zero in Celsius, Fahrenheit, and Kelvin?
Absolute zero is 0 K, −273.15°C, or −459.67°F. This is the coldest possible temperature where all molecular motion stops.
What is the freezing and boiling point of water in all three scales?
Water freezes at 0°C, 32°F, and 273.15 K. Water boils at 100°C, 212°F, and 373.15 K at standard atmospheric pressure.
How do you convert Fahrenheit to Kelvin?
First convert Fahrenheit to Celsius by subtracting 32 and multiplying by 5/9, then add 273.15. The direct formula is K = (°F − 32) × 5/9 + 273.15.