Fahrenheit to Celsius Converter

About the Fahrenheit to Celsius Converter

Convert any Fahrenheit temperature to Celsius with the standard formula: °C = (°F − 32) × 5/9. Enter a Fahrenheit value and review the Celsius and Kelvin equivalents.

Fahrenheit-to-Celsius is the most common temperature conversion worldwide. Non-American travelers interpreting US weather forecasts, international cooks using American oven settings, scientists converting data, and students learning thermodynamics all need this conversion regularly.

The Fahrenheit scale is used primarily in the United States for weather, cooking, and everyday temperature. Nearly all other countries use Celsius. This converter makes translation between the two direct and reliable.

When This Page Helps

Understanding Fahrenheit temperatures when you think in Celsius (or vice versa) is a daily need for travelers, cooks, and anyone reading American vs. international content.

How to Use the Inputs

1. Enter the Fahrenheit temperature.
2. The Celsius equivalent appears in the result panel.
3. Kelvin is also shown for scientific reference.
4. Use negative values for below-zero temperatures.
5. Check the reference table for common temperature benchmarks.

Example Calculation

Tips & Best Practices

• Quick estimate: subtract 30 and divide by 2 (gives rough Celsius for everyday weather temps).
• Key benchmarks: 32°F = 0°C, 72°F = 22°C, 98.6°F = 37°C, 212°F = 100°C.
• Oven temps: 350°F = 177°C, 375°F = 191°C, 400°F = 204°C, 425°F = 218°C.
• −40° is the same in both scales — the crossover point.
• Each Fahrenheit degree is smaller than a Celsius degree (1°F = 5/9°C).

The Fahrenheit Scale

Daniel Gabriel Fahrenheit developed his scale in 1724. He set 0° as the temperature of a brine solution and approximately 96° as body temperature. Water's freezing point (32°F) and boiling point (212°F) were later established as fixed points, giving a 180-degree span between them.

Why the Conversion Involves 32 and 5/9

The factor 5/9 comes from the ratio of Celsius degrees to Fahrenheit degrees between the two fixed points: 100°C span / 180°F span = 5/9. The offset of 32 accounts for the different zero points of the two scales.

Temperature in Daily Life

Weather forecasts, thermostat settings, cooking temperatures, and body temperature readings are the most common uses. Understanding the Fahrenheit scale helps when visiting the US, while understanding Celsius is essential everywhere else.

Frequently Asked Questions

• What is the formula for Fahrenheit to Celsius?

  The formula is °C = (°F − 32) × 5/9. Subtract 32 from the Fahrenheit value, then multiply by 5/9 (or equivalently, divide by 1.8). This formula is exact and works for all temperature values.

• What is 72°F in Celsius?

  72°F = 22.22°C. This is a typical comfortable room temperature. The calculation: (72 − 32) × 5/9 = 40 × 5/9 = 22.22°C.

• What is 100°F in Celsius?

  100°F = 37.78°C. This is slightly above normal body temperature (37°C = 98.6°F) and would indicate a mild fever. Calculation: (100 − 32) × 5/9 = 68 × 5/9 = 37.78°C.

• How do I quickly estimate Fahrenheit to Celsius?

  Subtract 30 and divide by 2. This gives a rough estimate: 72°F → (72−30)/2 = 21°C (actual: 22.2°C). It works reasonably well for everyday weather temperatures between 0°F and 100°F.

• What is 0°F in Celsius?

  0°F = −17.78°C. Fahrenheit zero was originally set as the temperature of a brine solution (ice, water, and ammonium chloride). It is well below the freezing point of water.

• Is 40°F cold?

  40°F = 4.44°C. Yes, this is cold — close to refrigerator temperature (35–40°F / 2–4°C). You would need a heavy jacket. It is above freezing but uncomfortably cold for most people.