1 °F = -17.222222 °C

Convert Fahrenheit to Celsius

Fahrenheit to Celsius

Preset to Fahrenheit to Celsius. Change the value, swap the direction, or pick any other pair of temperature units — the formula tile always shows the arithmetic being applied.

Conversions run in your browser against a fixed factor table.
Quick Answer • How do I convert Fahrenheit to Celsius?

°C = (°F − 32) × 5/9 — so 1 °F = -17.222222 °C and 72 °F = 22.222222 °C. Reversed, °F = (°C × 9/5) + 32, giving 1 °C = 33.8 °F.

Fahrenheit to Celsius using the same factor table the full converter uses. The formula is shown with the result, the table below works it through 9 values, and the reverse direction is one click away.

1. How to convert Fahrenheit to Celsius

Fahrenheit and Celsius do not share a zero point, so the conversion needs an offset as well as a ratio: °C = (°F − 32) × 5/9. That is an affine conversion, not a proportional one.

Worked at the two values people ask for most: 1 °F = -17.222222 °C and 72 °F = 22.222222 °C. Going the other way, °F = (°C × 9/5) + 32, so 1 °C = 33.8 °F — a direction with its own page, Celsius to Fahrenheit.

Results are given to eight significant figures. That is more precision than most jobs need — for a rough figure, treat 1 °F as about -17.222222 °C and adjust — but rounding early and multiplying afterwards is how a small error becomes a visible one, so the full figure is what the converter carries.

2. Fahrenheit to Celsius conversion table

Fahrenheit (°F)Celsius (°C)
-40 °F-40 °C
0 °F-17.777778 °C
32 °F0 °C
50 °F10 °C
68 °F20 °C
72 °F22.222222 °C
90 °F32.222222 °C
98.6 °F37 °C
212 °F100 °C

Every row is the same factor applied — nothing in the table is a special case, and any value in between behaves the same way. Type your own figure into the converter above and the Formula tile shows the arithmetic being used, so the result is checkable rather than taken on trust.

3. What the two units are

  • Fahrenheit (°F). Fahrenheit puts freezing at 32 and boiling at 212, so its degree is 5/9 the size of a Celsius one.
  • Celsius (°C). Celsius puts water’s freezing point at 0 and its boiling point at 100 at standard pressure.

Both scales are converted through kelvin internally, which is why the arithmetic handles negative values correctly — an offset applied in the wrong order is the usual source of a wrong answer here.

Temperature is the one category that needs an offset as well as a factor, because the scales do not share a zero. That has a consequence people trip over constantly: you cannot convert a temperature difference the same way you convert a temperature. A room at 20 °C is 68 °F, but a rise of 20 °C is a rise of 36 °F. For an interval, apply the 9/5 ratio and drop the offset.

If the pair you actually want is not this one, the full unit converter runs every 4 temperature units off the same factor table, along with 11 other categories of measurement.

Worth knowingSubtract 32 before multiplying, not after — that ordering is the most common arithmetic slip in this direction. 98.6 °F is 37 °C, and −40 °F is −40 °C.

4. Fahrenheit to Celsius FAQs

How do I convert Fahrenheit to Celsius?

Apply (°F − 32) × 5/9 — the scales need an offset as well as a ratio because they do not share a zero. 1 °F = -17.222222 °C, and 72 °F = 22.222222 °C.

What is 1 °F in °C?

1 °F = -17.222222 °C. The full formula is °C = (°F − 32) × 5/9, and 1 °C = 33.8 °F going the other way.

What is 72 °F in °C?

72 °F = 22.222222 °C. The table above works the same factor through 9 values, and the converter takes any figure you type — including decimals and negatives.

How do I convert Celsius to Fahrenheit?

°F = (°C × 9/5) + 32, so 1 °C = 33.8 °F. Use the Swap button in the converter to reverse the direction without retyping the value, or open the dedicated Celsius to Fahrenheit page.

Can I convert a temperature difference the same way?

No. The offset belongs to a point on the scale, not to an interval. A room at 20 °C is 68 °F, but a rise of 20 °C is a rise of 36 °F — for a difference you apply the 9/5 ratio and drop the +32. It is the most common temperature-conversion error in engineering copy.

Is anything I type sent to a server?

No. The factor table ships with the page and every conversion runs in your browser. Nothing is uploaded, logged or written to storage, and the converter keeps working offline once the page has loaded.