🌡️ Temperature Converter
Convert Celsius, Fahrenheit and Kelvin instantly — with a chart for weather, body and oven temperatures.
Common temperature conversions
| Value | °C | °F | K | Note |
|---|---|---|---|---|
| −273.15 °C | −273.15 | −459.67 | 0 | absolute zero |
| −40 °C | −40 | −40 | 233.15 | where °C and °F are equal |
| 0 °F | −17.778 | 0 | 255.37 | freezer (0 °F) |
| 0 °C | 0 | 32 | 273.15 | water freezes |
| 40 °F | 4.4444 | 40 | 277.59 | refrigerator (40 °F or below) |
| 68 °F | 20 | 68 | 293.15 | room temperature |
| 98.6 °F | 37 | 98.6 | 310.15 | traditional "normal" body temperature |
| 100.4 °F | 38 | 100.4 | 311.15 | common fever threshold |
| 100 °C | 100 | 212 | 373.15 | water boils (sea level) |
| 350 °F | 176.67 | 350 | 449.82 | oven baking |
How to use the temperature converter
Enter a temperature and choose its unit; the other two units appear instantly. Use it for weather forecasts, recipes, thermostat settings or science homework. For one direction only, the Celsius to Fahrenheit and Fahrenheit to Celsius pages include detailed charts.
The three temperature scales
| Unit | Symbol | Definition |
|---|---|---|
| Celsius | °C | Water freezes at 0 and boils at 100 (sea level) |
| Fahrenheit | °F | Water freezes at 32 and boils at 212 |
| Kelvin | K | Absolute zero = 0 K = −273.15 °C |
- Celsius (°C) — water freezes at 0 and boils at 100. Used by almost every country and in science.
- Fahrenheit (°F) — water freezes at 32 and boils at 212, with 180 degrees between them. Used for everyday temperatures in the United States and a few other places.
- Kelvin (K) — the SI unit, starting at absolute zero. One kelvin is the same size step as one degree Celsius. It is written without a degree sign: 300 K.
Temperature conversion formulas
°F = °C × 9/5 + 32 °C = (°F − 32) × 5/9 K = °C + 273.15
Unlike length or weight, temperature scales have different zero points, so you cannot convert with multiplication alone. When converting a temperature difference, though, skip the 32: a rise of 10 °C is a rise of 18 °F (10 × 9/5). This calculator converts temperature values, so for differences just multiply or divide by 1.8.
Mental-math shortcuts
Celsius to Fahrenheit: double it and add 30. Fahrenheit to Celsius: subtract 30 and halve it. Both are within a few degrees for everyday weather (0–30 °C / 32–86 °F). Also remember that −40 is the one temperature where both scales agree — a useful check.
Easy reference points
0 °C = 32 °F (freezing), 10 °C = 50 °F (cool), 20 °C = 68 °F (room temperature), 30 °C = 86 °F (hot), 37 °C = 98.6 °F (body temperature), 100 °C = 212 °F (boiling).
Fever thresholds depend on where and how temperature is measured. This chart is for unit conversion and is not medical advice.