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Fahrenheit to Celsius Converter
↔ Convert °C to °F instead

Common Conversions

°F °C
-459.67 -273.15
-320.8 -196
-40 -40
0 -17.78
32 0
68 20
77 25
98.6 37
212 100
392 200
572 300
932 500
1832 1000

Why this conversion matters in chemistry

Fahrenheit mostly disappears once you leave the US, but it sticks around in older American literature and on equipment that was built to ship into that market. An autoignition temperature of 451°F, for example, works out to about 233°C — and if you're comparing against a modern DSC trace or an IUPAC reference table, you need it in Celsius to be useful. Subtract 32, then multiply by 5/9. The subtraction is the part that trips people up, because it handles the offset between where the two scales put zero, and getting it out of order gives you a number that's in the right neighborhood but meaningfully wrong.

Formula

°C = (°F − 32) × 5/9

Worked Examples

212°F = 100°C

Boiling water. The cleanest anchor in the whole scale and the easiest way to sanity-check a thermometer.

32°F = 0°C

Water's freezing point. Where the Celsius scale puts its zero, and where Fahrenheit puts its awkward 32.

98.6°F = 37°C

Body temperature. Any mammalian cell culture or enzyme assay is calibrated to this number.

451°F = 232.8°C

Roughly where paper autoignites — a classic materials-science reference point, made famous by a novel.

Frequently Asked Questions

How do I convert Fahrenheit to Celsius?
Subtract 32 first, then multiply by 5/9. For 212°F, that's (212 − 32) × 5/9 = 180 × 5/9 = 100°C. Order matters: if you multiply before subtracting, the offset ends up in the wrong place and you'll get a number that looks plausible but is off by a constant.
Why does chemistry prefer Celsius?
Because Celsius lines up with Kelvin — K = °C + 273.15 — and Kelvin is what gas laws, equilibrium constants, and rate expressions actually want. You can't put Fahrenheit into the ideal gas law without converting first, so the field standardized on the scale that makes the arithmetic work.
What's absolute zero in Fahrenheit?
−459.67°F. That's 0 K or −273.15°C — the temperature where classical molecular motion stops. A useful number to have memorized, mostly so you can recognize when a conversion has drifted somewhere deeply implausible.