Convert Fahrenheit to Celsius

450 degrees Fahrenheit in every temperature unit

Each scale is defined off the kelvin, so these are exact relations rather than measured ones — only the display is rounded.

How do you convert degrees Fahrenheit to degrees Celsius? The converter and the working

1. 1.Take the temperature in degrees Fahrenheit.
2. 2.Apply (°F − 32) × 5/9 — the two scales differ in where zero sits as well as in how big a degree is, so this is a line rather than a single multiplication.
3. 3.Sanity-check against a fixed point: 32 °F is 0 °C, where water freezes.

Worked example: 25 degrees Fahrenheit to degrees Celsius

Formula

(°F − 32) × 5/9 = °C

Arithmetic

(25 − 32) × 5/9 = -3.89 °C

Answer

25 °F = -3.89 °C

The relation is exact by definition — both scales are fixed to the kelvin — so only the display is rounded.

Degrees Fahrenheit to degrees Celsius conversion table

What is a degree Fahrenheit?

The US everyday scale, with water freezing at 32 and boiling at 212 — 180 degrees apart, which is why a Fahrenheit degree is exactly five ninths of a Celsius one. Daniel Fahrenheit set his zero at the coldest temperature he could reproduce in 1724, a brine ice bath.

What is a degree Celsius?

The everyday metric scale, with zero at the freezing point of water and 100 at its boiling point under standard pressure. Since 2019 it has been defined off the kelvin rather than off water: 0 °C is exactly 273.15 K.

The points to check a conversion against

water freezes at 32 °F, which is 0 °C; body temperature at 98.6 °F, which is 37 °C; water boils at 212 °F, which is 100 °C. Absolute zero is -459.67 °F and -273.15 °C — nothing is colder, which is why a converter returning a temperature below it is wrong rather than merely cold.

Every temperature unit here

The whole group — 4 units with their symbols and the size of each one in kelvins — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a degree Fahrenheit.

Source: NIST — the kelvin and the International Temperature Scale

Cite this page

APA

Rule Calculator. (2026). Convert Degrees Fahrenheit to degrees Celsius. Rule Calculator. https://rulecalculators.com/convert/fahrenheit-to-celsius

MLA

"Convert Degrees Fahrenheit to degrees Celsius." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/fahrenheit-to-celsius.

Chicago

Rule Calculator. "Convert Degrees Fahrenheit to degrees Celsius." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/fahrenheit-to-celsius.

The date is when the figures on this page were last checked against their source, not the day you opened it. Add your own access date if your style needs one.

Questions people actually ask

What is the formula to convert degrees Fahrenheit to degrees Celsius?

(°F − 32) × 5/9. Unlike every other conversion on this site, this is not a multiplication: the two scales put zero in different places, so the shift matters as much as the step size.

What is 32 °F in degrees Celsius?

0 °C. That is the freezing point of water, and it is the fastest way to check any converter — including this one.

Where do the Celsius and Fahrenheit scales meet?

At −40. It is the one reading where the two scales agree, which is why "forty below" needs no unit. In kelvins that point is 233.15 K, and in Rankine 419.67 °R.

What is absolute zero in degrees Celsius?

-273.15 °C. Nothing can be colder: it is the point where a system holds no thermal energy to give up, and the kelvin and Rankine scales both start there rather than at an arbitrary reference.

The values people look up

Each one is this page with the value filled in, and each answers in its own title.

Other temperature conversions

Degrees Celsius to degrees Fahrenheit — the same conversion the other way.

Calculators that work in temperature