# How to convert Fahrenheit to Celsius?

Converting Fahrenheit to Celsius doesn't require a calculator. Here are some easy-to-remember temperatures if you're accustomed to Fahrenheit temperatures...

• 10F is approximately -10C
• 32F = 0C (melting point of water)
• 40F is approximately 4C
• 70F is approximately 20C
• 100F is approximately 40C

## Converting Fahrenheit to Celsius

1. Take your Fahrenheit temperature, and subtract 32 from it. Let's say the temperature is 50F. Our result is then 50 - 32 = 18.
2. Multiply the result by 5. In our example, we do the multiplication and get 18 x 5 = 90.
3. Divide the result by 9 to get our final Celsius result, 90/9 = 10C.

Fahrenheit to Celsius formula: (F-32) * 5 / 9 = C

## Convert Celsius to Fahrenheit

1. Take your Celsius temperature, and multiply by 9. Let's say the temperature is 25C. Our result is then 25 * 9 = 225.
2. Divide the result by 5. In our example, we do the division and get 225 / 5 = 45.
3. Add 32 to the result to get our final Fahrenheit result, 45 + 32 = 77.

Celsius to Fahrenheit formula: C * 9/5 + 32 = F

## Why is -40F = -40C?

Oddly enough, -40F is not colder than -40C. Yes, they are both really cold, but they are also exactly the same temperature. Let's use the formulas from above and try it out.

Convert -40F to Celsius

1. (F-32) * 5 / 9
2. (-40-32) * 5 / 9
3. -72 * 5 / 9 = -40

Convert -40C to Fahrenheit

1. (C * 9 / 5) + 32
2. (-40 * 9 / 5) + 32
3. -72 + 32 = -40

Exactly the same!