Temperature Converter
Free online temperature converter. Convert between Celsius, Fahrenheit, and Kelvin with reference points and live updates.
How to Use the Temperature Converter
Enter a temperature and select Celsius, Fahrenheit, or Kelvin. All three values update simultaneously.
About This Tool
Celsius, Fahrenheit, and Kelvin are the three temperature scales you will encounter in everyday life and science. Celsius is used by most of the world for weather and cooking. Fahrenheit is standard in the United States for weather and oven temperatures. Kelvin is the SI unit used in science — it starts at absolute zero (−273.15 °C), the coldest physically possible temperature, making it essential for physics and chemistry. Unlike length or weight conversions, temperature conversion is not a simple ratio — it involves both multiplication and an offset, which is why mental math often goes wrong. This tool converts all three scales simultaneously with a quick reference table for common benchmarks.
Quick Reference Table
| Celsius | Fahrenheit | Kelvin | Note |
|---|---|---|---|
| -40°C | -40°F | 233.15 K | Crossover point |
| 0°C | 32°F | 273.15 K | Water freezing |
| 20°C | 68°F | 293.15 K | Room temperature |
| 37°C | 98.6°F | 310.15 K | Body temperature |
| 100°C | 212°F | 373.15 K | Water boiling |
| 180°C | 356°F | 453.15 K | Baking low |
| 200°C | 392°F | 473.15 K | Baking medium |
| 220°C | 428°F | 493.15 K | Baking high |
Frequently Asked Questions
How do I convert Celsius to Fahrenheit?
Multiply the Celsius value by 9/5, then add 32. For example, 25°C = (25 × 9/5) + 32 = 77°F. This converter handles both directions instantly.
Is this temperature converter accurate?
Yes. It uses the exact mathematical formulas for converting between Celsius, Fahrenheit, and Kelvin.
Does this converter work on mobile?
Yes. It is fully responsive and works on phones, tablets, and desktops.
Do I need to sign up to use this tool?
No. Completely free, no account needed.
Why do Celsius and Fahrenheit meet at -40°?
The formulas °F = (°C × 9/5) + 32 and °C = (°F − 32) × 5/9 produce a crossover point where both scales read the same value. Solving °C = (°C × 9/5) + 32 gives °C = −40. This is the only temperature where Celsius and Fahrenheit are equal.
What is the difference between Kelvin and Celsius?
Kelvin and Celsius use the same degree size — a one-degree change in Celsius equals a one-degree change in Kelvin. The only difference is the zero point: 0 K is absolute zero (−273.15 °C), while 0 °C is the freezing point of water. To convert, add or subtract 273.15.