-20 Fahrenheit to Celsius
-28.9 °C
-20 °F = -28.9 °C.
Celsius
-28.9°C
-20 °F = -28.9 °C
The short answer
How many Celsius is -20 Fahrenheit?
-20 °F = -28.9 °C. 1 Fahrenheit = 0.555556 Celsius, then − 17.77777777777778, so the working is -20 × 0.555556 − 17.7778 = -28.9.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 Fahrenheit = 0.555556 Celsius, then − 17.77777777777778 -20 × 0.555556 − 17.7778 = -28.9
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (°C) | Off by |
|---|---|---|
| Whole number | -29 | −0.11111 |
| 1 decimal | -28.9 | −0.01111 |
| 2 decimals | -28.89 | −0.00111 |
Round trip: take -28.9 °C back the other way and you land on -20.0200 °F — a drift of 0.0200 °F. That gap is the rounding, not the conversion.
Frequently asked questions
What is -20 Fahrenheit in Celsius?
-20 Fahrenheit is -28.9 Celsius. 1 Fahrenheit = 0.555556 Celsius, then − 17.77777777777778, so the working is -20 × 0.555556 − 17.7778 = -28.9.
How accurate is -28.9 °C?
Rounding to -28.9 °C and converting straight back gives -20.0200 °F, a drift of 0.0200 °F from the -20 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
Fahrenheit to Celsius Converter
Convert Fahrenheit to Celsius — fevers, recipes, and forecasts abroad.
Open the fahrenheit to celsius converter →