Fahrenheit to Celsius Converter
Convert °F to °C instantly — type in either box and the answer appears as you type.
100°F = 37.78°C
The formula
°C = (°F − 32) × 5/9
Example: 100°F converts to 37.8°C — 100 − 32 = 68, 68 × 5/9 = 37.8°C.
Fahrenheit to Celsius conversion table
Reading Fahrenheit weather in Celsius
Subtract 30, halve it — that is the estimate for converting °F to °C in your head, and for weather temperatures it lands within a degree or two. 70°F becomes 'about 20°C' (exact: 21.1), 90°F becomes 'about 30°C' (exact: 32.2). Good enough to decide whether you need a jacket; not good enough for a science lab, which is what the calculator above is for.
The comfort anchors Americans grow up with translate cleanly: 60s°F = teens °C (cool), 70s°F = low 20s °C (pleasant), 80s°F = high 20s °C (warm), 90s°F = low-to-mid 30s °C (hot). Once those four bands are internalized, US weather forecasts stop being a puzzle — and 'it hit 100 today' resolves to the genuinely alarming 37.8°C.
Cooking temperatures without the guesswork
Recipe conversion is where Fahrenheit-to-Celsius precision matters most, because oven dials are coarse and baking is chemical. The three numbers that cover most recipes: 350°F → 175°C, 375°F → 190°C, 425°F → 220°C. Meat thermometers add one more — 165°F / 74°C for poultry safety, a number public-health agencies print on both scales for exactly this reason.
Candy making and deep frying are stricter still: stages like 'soft ball' (240°F / 115°C) and 'hard crack' (300°F / 150°C) sit within 5-degree windows, so a thermometer that reads in the wrong unit without conversion ruins the batch. Sugar chemistry does not care which scale you grew up with — it changes state at fixed temperatures, and this converter is how you meet it on its terms.
Common Fahrenheit to Celsius values
Weather & comfort
Oven & baking
How do you convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit temperature, then multiply by 5/9: °C = (°F − 32) × 5/9. For example, (100°F − 32) × 5/9 = 37.8°C.
What is the fastest way to estimate Fahrenheit to Celsius?
Subtract 30 from the Fahrenheit number and divide by 2. For 80°F that gives roughly 25°C (the exact answer is 26.7°C) — good enough for everyday weather.
What is 98.6°F in Celsius?
98.6°F equals 37°C — the classic value for normal human body temperature.
At what temperature are Celsius and Fahrenheit equal?
At −40 degrees: −40°C = −40°F. It is the one point where the two scales meet.