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How to Convert Celsius to Fahrenheit

4 min read

Whether you're travelling to the US, following a recipe, or just checking the weather, knowing how to convert between Celsius and Fahrenheit is a life skill. Here's everything you need.

The Formula

ยฐF = (ยฐC ร— 9/5) + 32

Or equivalently: ยฐF = (ยฐC ร— 1.8) + 32

Quick Mental Math Trick

Don't have a calculator? Use this shortcut that gets you within 1-2 degrees:

  1. Double the Celsius number
  2. Subtract 10% of that result
  3. Add 32

Example: 25ยฐC โ†’ 25ร—2 = 50 โ†’ 50โˆ’5 = 45 โ†’ 45+32 = 77ยฐF โœ“

Going the Other Way: Fahrenheit to Celsius

ยฐC = (ยฐF โˆ’ 32) ร— 5/9

Example: 98.6ยฐF โ†’ (98.6โˆ’32) ร— 5/9 = 66.6 ร— 0.556 = 37ยฐC (body temperature)

Common Temperatures Reference

Description ยฐC ยฐF
Water freezes 0 32
Cool room 18 64
Comfortable room 22 72
Hot day 35 95
Body temperature 37 98.6
Fever 39 102
Water boils 100 212
Oven (moderate) 180 356

Why Two Systems?

Celsius (also called Centigrade) is based on water: 0ยฐ = freezing, 100ยฐ = boiling. It's used by every country except the US, Liberia, and Myanmar.

Fahrenheit was created earlier (1724) by Daniel Fahrenheit. In his scale, 0ยฐ was the coldest temperature he could create in a lab, and 96ยฐ was body temperature (later refined to 98.6ยฐ).

When Does It Matter?

  • โ–ถ Cooking: US recipes use ยฐF, European ones use ยฐC
  • โ–ถ Weather: "It's 100ยฐF" sounds extreme to a European (it's 38ยฐC)
  • โ–ถ Medicine: A fever is 38ยฐC / 100.4ยฐF โ€” know both
  • โ–ถ Science: Always Celsius (or Kelvin)

Try It Now

Use our Temperature Converter for instant, accurate conversions between Celsius, Fahrenheit, and Kelvin.

๐Ÿ”— Try our free temperature converter

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