Celsius to Fahrenheit Conversion: Formula, Chart, and Quick Tips

The Celsius to Fahrenheit Formula

The exact conversion formula from Celsius to Fahrenheit:

°F = (°C × 9/5) + 32

Or equivalently: °F = (°C × 1.8) + 32

The exact conversion from Fahrenheit to Celsius:

°C = (°F − 32) × 5/9

Or equivalently: °C = (°F − 32) ÷ 1.8

Key Temperature Reference Points

Event

Celsius

Fahrenheit

|---|---|---|

Water freezes	0°C	32°F
Cold day	10°C	50°F
Room temperature	22°C	71.6°F
Body temperature	37°C	98.6°F
Hot summer day in Delhi	45°C	113°F
Water boils (sea level)	100°C	212°F
Baking (moderate oven)	180°C	356°F
Baking (hot oven)	220°C	428°F

Mental Math Shortcut

For a quick rough conversion without needing exact precision:

Celsius to Fahrenheit: Double the Celsius and add 30.

Example: 25°C → (25 × 2) + 30 = 80°F (actual: 77°F)

This approximation is within 5% for temperatures between 0°C and 40°C — accurate enough for everyday use like understanding weather forecasts.

Why Two Different Scales Exist

Fahrenheit was proposed by German physicist Daniel Gabriel Fahrenheit in 1724. He set 0°F as the coldest temperature he could achieve with a salt-ice mixture and 96°F as human body temperature (later adjusted to 98.6°F).

Celsius was proposed by Swedish astronomer Anders Celsius in 1742. His scale set 0° as water's freezing point and 100° as boiling point — a clean, scientifically logical scale.

Most countries adopted Celsius (the metric system). The United States retained Fahrenheit, making conversion necessary for international communication.

When Celsius to Fahrenheit Matters

Weather: US weather apps and news report in Fahrenheit. International travellers to the US need to convert.

Cooking: US recipes use Fahrenheit. Indian and European recipes use Celsius.

Medical: Body temperature 37°C = 98.6°F normal. A fever of 38.5°C = 101.3°F.

Science: Scientific work universally uses Celsius or Kelvin.