Fahrenheit to Celsius Converter
Convert Fahrenheit to Celsius instantly. Formula: (°F − 32) × 5/9. Understand weather forecasts, oven temperatures, and fever readings when switching between US and metric systems.
Why Use Fahrenheit to Celsius Converter
Americans traveling abroad, international visitors to the US, and anyone working with US temperature data needs a reliable Fahrenheit to Celsius converter. When a US recipe says 375°F, an international recipe says 200°C — these are nearly the same oven setting, but without conversion you'd never know. When a US weather forecast says 95°F, that's 35°C — a heat warning in most of the world. The formula (°F − 32) × 5/9 is too cumbersome for quick mental math, making this converter indispensable for daily use.
- Cooking and baking: Convert US oven temperatures to Celsius for metric appliances
- Weather interpretation: Understand US temperature forecasts in familiar Celsius terms
- Medical: Convert body temperature readings between US and international formats
- Science and education: Work with US temperature data in metric contexts
- Engineering: Convert US-spec thermal requirements to metric system values
Quick Reference: Common Conversions
- 32°F = 0°C (water freezes)
- 50°F = 10°C (cool weather)
- 68°F = 20°C (room temperature)
- 77°F = 25°C (warm room / mild summer)
- 86°F = 30°C (hot summer day)
- 98.6°F = 37°C (normal body temperature)
- 212°F = 100°C (water boils)
- 350°F = 176.7°C (standard baking temperature)
The Formula
To convert Fahrenheit to Celsius, subtract 32 then multiply by 5/9 (or divide by 1.8):
°C = (°F − 32) × 5/9
For a quick mental estimate: subtract 30 and divide by 2. For example, 72°F: (72 - 30) ÷ 2 = 21°C (actual: 22.2°C). This approximation works well for weather temperatures in the 50°F–100°F range. For precise values — especially cooking and medical — use the exact formula or this converter.
Real-World Examples
- US recipe: Bake at 350°F = 176.7°C — round up to 180°C on a metric oven.
- Summer heat: A 100°F day equals 37.8°C — the same temperature as the human body.
- Fever: A 103°F fever equals 39.4°C — a high fever requiring medical attention.
- Cold snap: 14°F (-10°C) is well below freezing — pipes can burst at this temperature.
- Swimming pool: An 80°F pool equals 26.7°C — the standard competition temperature for Olympic swimming.
Frequently Asked Questions
What is the formula to convert Fahrenheit to Celsius?
The exact formula is °C = (°F − 32) × 5/9. Step by step: subtract 32 from the Fahrenheit value, then multiply by 5 and divide by 9 (or multiply by 0.5556). For example, 212°F: 212 - 32 = 180, × 5 = 900, ÷ 9 = 100°C. This formula reverses the Celsius-to-Fahrenheit conversion. The scale ratio 5/9 reflects that each Celsius degree is 1.8 times larger than a Fahrenheit degree. The −32 offset corrects for Fahrenheit's freezing point being at 32 instead of 0.
What is 72 degrees Fahrenheit in Celsius?
72°F equals 22.2°C. This is a very pleasant, comfortable temperature — what most people would describe as a perfect room temperature or an ideal spring day. In US buildings, 72°F is a common thermostat setting for year-round comfort. Many offices and homes in the US target 70–72°F (21.1–22.2°C) for heating and cooling. Internationally, the equivalent comfort zone of 20–22°C is likewise considered ideal for productivity and comfort.
What is 100°F in Celsius?
100°F equals 37.8°C. This temperature is significant for two reasons: it's the approximate threshold of a fever in adults (normal body temperature is 98.6°F / 37°C, and 100°F is often cited as the low-grade fever boundary), and it's also a hot summer day temperature in many parts of the US Southwest. In outdoor terms, 100°F (37.8°C) is dangerously hot — the US National Weather Service issues heat advisories when temperatures reach this level, especially combined with high humidity.
What temperature should I set my oven in Celsius for Fahrenheit recipes?
Use this practical guide: 325°F = 165°C (slow/low), 350°F = 177°C (moderate, round to 180°C), 375°F = 190°C (moderately hot), 400°F = 205°C (hot, round to 200°C), 425°F = 220°C (very hot), 450°F = 232°C (high heat). For most baking, rounding to the nearest 5 or 10°C is fine — home ovens are rarely accurate to within 5°C anyway. If your oven has a fan (convection), reduce temperature by about 20°C (or 25°F) from the stated temperature.