Temperature Converter
Convert Celsius, Fahrenheit, and Kelvin with reversible formulas and examples. Fully client-side — no account, uploads, or remote storage.
Added Apr 18, 2026 · Updated May 1, 2026
Input
Result
Enter a value for temperature to see your result.
How it works
Converts a temperature between Celsius, Fahrenheit, and Kelvin simultaneously. Enter a value in any unit and instantly see the equivalent in all three scales.
Formula
°F = °C × 9/5 + 32 | K = °C + 273.15
- °C
- Temperature in Celsius
- °F
- Temperature in Fahrenheit
- K
- Temperature in Kelvin
Step by step
- 01Enter a temperature value and select the source unit.
- 02The tool first converts to Celsius as an intermediate step.
- 03From Celsius: °F = °C × 9/5 + 32, K = °C + 273.15.
- 04All three results are shown simultaneously.
Examples
Boiling point of water
Water boils at 100°C, 212°F, or 373.15 K at standard atmospheric pressure.
Inputs
- Temperature:
- 100
- From:
- C
Result
- Celsius (°C):
- 100 °C
- Fahrenheit (°F):
- 212 °F
- Kelvin (K):
- 373.15 K
Body temperature
Normal human body temperature is 98.6°F = 37°C.
Inputs
- Temperature:
- 98.6
- From:
- F
Result
- Celsius (°C):
- 37 °C
- Fahrenheit (°F):
- 98.6 °F
- Kelvin (K):
- 310.15 K
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5 (or 1.8) and then add 32. For example: 20°C × 1.8 + 32 = 68°F.
What is absolute zero in Celsius?
Absolute zero — the lowest possible temperature — is −273.15°C (−459.67°F or 0 K).
Why do news reports use °C but my thermostat uses °F?
They are linearly related but anchored differently. Scientists and most countries use Celsius for water-centric reference points; the US still commonly uses Fahrenheit for weather and HVAC.
Are color temperature (Kelvin for light bulbs) the same as thermodynamic Kelvin?
They share the same unit name, but lighting 'Kelvin' describes the hue of a black-body radiator approximation, not the air temperature in your room. Do not mix lighting K with weather conversions.
Can rounding cause 0.1° disagreements between tools?
Yes. Intermediate rounding, float precision, and whether you convert via Kelvin first can shift the last digit. For engineering, carry extra precision until the final display step.