How to Convert Celsius to Fahrenheit — Step-by-Step Guide

Convert Celsius to Fahrenheit: Quick Formula & Examples

Converting temperatures between Celsius (°C) and Fahrenheit (°F) is a common task in cooking, travel, science, and everyday life. This article gives the simple formula, a quick mental shortcut, worked examples, and a small reference table for common temperatures.

Quick Formula

• To convert Celsius to Fahrenheit: F = (C × ⁄₅) + 32

• To convert Fahrenheit to Celsius: C = (F − 32) × ⁄₉

Why the formula works (brief)

The Celsius and Fahrenheit scales use different zero points and different sized degrees. Multiplying by ⁄₅ (or 1.8) scales the size of the degree; adding 32 shifts the zero point.

Step-by-step examples

1. Example — 0°C to °F
   F = (0 × ⁄₅) + 32 = 32°F

2. Example — 100°C to °F
   F = (100 × ⁄₅) + 32 = (100 × 1.8) + 32 = 180 + 32 = 212°F

3. Example — 20°C to °F
   F = (20 × ⁄₅) + 32 = (20 × 1.8) + 32 = 36 + 32 = 68°F

4. Example — -10°C to °F
   F = (-10 × ⁄₅) + 32 = (-10 × 1.8) + 32 = -18 + 32 = 14°F

5. Example — 37°C (body temperature) to °F
   F = (37 × ⁄₅) + 32 = (37 × 1.8) + 32 = 66.6 + 32 = 98.6°F

Quick mental shortcut

• Multiply the Celsius by 2, add 30 — gives a rough Fahrenheit estimate.
  • Example: 20°C → (20×2)+30 = 70°F (actual 68°F).
• For better accuracy: (C × 2) + 30 − (C ÷ 6).
  • Example: 20°C → 40 + 30 − 3.3 = 66.7°F (very close).

Handy reference table

Tips

• Use the exact formula for scientific calculations or precise cooking/baking.
• Use the mental shortcut for quick estimates while traveling or reading weather reports.
• Many devices let you switch units — use that when available to avoid manual conversion.

Small code snippet (JavaScript)

javascript
Copy CodeCopied
function cToF(c) {
return (c * 9/5) + 32;
}

That’s all you need to convert Celsius and Fahrenheit quickly and accurately.