Celsius to Fahrenheit Calculator
Convert a temperature in Celsius (°C) to Fahrenheit (°F). Enter a Celsius reading and the calculator returns the Fahrenheit value used in US weather forecasts, ovens, and thermostats.
How It Works
The two scales differ in two ways, and the formula corrects for both. Multiplying by 9/5 rescales the size of a degree, because there are 180 Fahrenheit degrees between freezing and boiling versus 100 Celsius degrees. Adding 32 then shifts the starting point, since water freezes at 0°C but at 32°F. Unlike the weight and distance conversions, temperature has a non-zero offset, so you cannot simply multiply by a single factor. The two scales read the same only at −40 degrees, where −40°C equals −40°F.
Worked Examples
Example 1 — body temperature. 37°C: (37 × 9/5) + 32 = 66.6 + 32 = 98.6°F.
Example 2 — freezing point. 0°C: (0 × 9/5) + 32 = 32°F.
When to Use This Calculator
Use this conversion when an international weather report or recipe gives Celsius and you think in Fahrenheit, when you read a metric thermometer, or when you set a US oven from a recipe written in Celsius. It is also useful for judging whether a foreign forecast means a warm or cold day.
| Celsius | Fahrenheit |
|---|---|
| -40 °C | -40 °F |
| 0 °C | 32 °F |
| 10 °C | 50 °F |
| 20 °C | 68 °F |
| 30 °C | 86 °F |
| 37 °C | 98.6 °F |
| 100 °C | 212 °F |
Frequently Asked Questions
What is 100°C in Fahrenheit?
Applying the formula gives (100 × 9/5) + 32 = 212°F, which is the boiling point of water at sea level.
What is a quick way to estimate Celsius in Fahrenheit?
Double the Celsius value and add 30. For example, 20°C becomes 40 plus 30, or about 70°F, close to the exact 68°F.
Why does the Celsius formula add 32 instead of just multiplying?
The scales start at different points — water freezes at 0°C but 32°F — so after rescaling the degree size you must add 32 to line the two scales up.