Celsius to Fahrenheit: Everything You Need to Know
Celsius (°C) and Fahrenheit (°F) are the two temperature scales most people encounter daily. The US uses Fahrenheit for weather and everyday temperature; almost every other country uses Celsius. Knowing how to convert between them is genuinely useful — especially when travelling, cooking international recipes, or following medical guidance.
The Conversion Formula
To convert Celsius to Fahrenheit:
°F = (°C × 9/5) + 32Equivalently: multiply by 1.8, then add 32.
Quick Reference Table
- −40 °C = −40 °F (the only point where both scales meet)
- 0 °C = 32 °F (water freezes)
- 20 °C = 68 °F (comfortable room temperature)
- 37 °C = 98.6 °F (normal body temperature)
- 100 °C = 212 °F (water boils at sea level)
A Quick Mental Shortcut
For a rough estimate: double the Celsius value and add 30. This gives you a result within a few degrees for the everyday range of −10 °C to 40 °C. For example, 20 °C → 40 + 30 = 70 °F (actual: 68 °F). Close enough for weather conversations.
Why Two Scales Exist
Celsius is based on the freezing (0 °C) and boiling (100 °C) points of water at standard pressure — intuitive for science and everyday use. Fahrenheit was defined earlier, with 0 °F set to the lowest temperature Daniel Fahrenheit could reliably reproduce with a salt/ice mixture, and 96 °F approximating body temperature. The US, Belize, and a few territories still use Fahrenheit exclusively.
Common Use Cases
- Converting weather forecasts when travelling to the US or following a US weather app
- Oven temperatures in American cookbooks (most US recipes use °F)
- Medical temperature readings when communicating between systems
- Setting thermostats in US homes if you're used to Celsius
Convert any temperature instantly: Free Celsius to Fahrenheit converter