Key Temperatures in Fahrenheit and Celsius: Body, Weather, and Oven Reference
October 21, 2026
The exact formulas are °F = °C × 9/5 + 32 and °C = (°F − 32) × 5/9. A normal body temperature of 37°C is 37 × 1.8 + 32 = 98.6°F, water boils at 100°C (212°F) at sea level, and a 350°F oven is (350 − 32) ÷ 1.8 = 176.7°C, which recipes round to 175 or 180°C. The two scales read the same at −40.
Skip the math and get your answer instantly:
Open the Temperature Converter →Reference Table
Memorizing a few anchor points makes it easier to judge temperatures in either unit.
| Situation | °C | °F |
|---|---|---|
| Water freezes | 0 | 32 |
| Cool day | 10 | 50 |
| Room temperature | 20 | 68 |
| Warm day | 30 | 86 |
| Normal body temperature | 37 | 98.6 |
| Fever (common threshold) | 38 | 100.4 |
| Water boils (sea level) | 100 | 212 |
| Moderate oven | 180 | 356 |
| Hot oven | 220 | 428 |
The Mental Shortcut
To estimate Fahrenheit from Celsius, double it and add 30. For 20°C: 40 + 30 = 70°F (the exact value is 68). For 30°C: 60 + 30 = 90°F (exact: 86). The error grows with temperature, reaching 4°F at 30°C. To go from Fahrenheit to Celsius, subtract 30 and halve: 70°F gives 20°C (exact: 21.1).
For better accuracy, subtract 2% to 10% from the doubled value, or use the exact formula when it matters, such as for cooking, lab work, or medical readings.
Oven Temperatures
Recipes written for fan ovens usually call for temperatures about 20°C (25 to 30°F) lower than those written for conventional ovens. Common conversions: 325°F ≈ 160–165°C, 350°F ≈ 175–180°C, 375°F ≈ 190°C, 400°F ≈ 200°C, and 425°F ≈ 218–220°C.
Gas mark settings, used in the UK, give another scale: gas mark 4 corresponds to 180°C (350°F).
Frequently Asked Questions
At what temperature are Celsius and Fahrenheit equal?
−40 degrees.
What is 350°F in Celsius?
About 177°C, usually rounded to 175 or 180°C in recipes.
How do I convert Celsius to Fahrenheit quickly?
Double the Celsius figure and add 30 for a rough estimate. Use ×1.8 + 32 for the exact answer.
What is normal body temperature?
About 37°C (98.6°F), though it varies slightly between people and across the day.