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Celsius to Fahrenheit Calculator

Convert any temperature between Celsius and Fahrenheit instantly. Type in either field for a live two-way result — includes a colour-coded feel indicator, Kelvin conversion and a full common temperature reference table.

✅ Free 🌡️ Two-Way Conversion ⚡ Instant Results 🔒 No Sign-Up
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Celsius ↔ Fahrenheit Calculator
Type in either field for an instant two-way temperature conversion
Celsius
°C
Fahrenheit
°F
Celsius
Fahrenheit
Kelvin
🌡️ Common Temperature Reference
°C°FDescription

How to Convert Celsius to Fahrenheit

To convert Celsius to Fahrenheit, multiply the temperature by 9, divide by 5, then add 32. This formula converts any temperature on the Celsius scale to its exact Fahrenheit equivalent.

°C to °F Formula
°F = (°C × 9 ÷ 5) + 32
Example: 25°C × 9 ÷ 5 = 45, then 45 + 32 = 77°F
°F to °C Formula (reverse)
°C = (°F − 32) × 5 ÷ 9
Example: (98.6°F − 32) × 5 ÷ 9 = 66.6 × 0.556 = 37°C
💡 Quick estimate: Double the Celsius temperature and add 30 for a rough Fahrenheit figure. For example, 20°C → 20 × 2 = 40, + 30 = 70°F (exact answer is 68°F). Good enough for a quick mental check.

Common Celsius to Fahrenheit Conversions

Celsius (°C)Fahrenheit (°F)What It Feels Like
−40°C−40°FExtreme cold — dangerous
0°C32°FFreezing point of water
10°C50°FVery cold — heavy coat needed
15°C59°FCool — jacket weather
20°C68°FComfortable room temperature
25°C77°FWarm — t-shirt weather
30°C86°FHot summer day
37°C98.6°FNormal human body temperature
40°C104°FExtreme heat / high fever
100°C212°FBoiling point of water

Celsius vs Fahrenheit — Key Differences

Celsius and Fahrenheit are two temperature scales with different zero points and intervals. Celsius is the standard in most countries and is part of the metric system. Fahrenheit is primarily used in the United States.

  • Celsius — water freezes at 0°C and boils at 100°C. Used in most countries, science, and medicine worldwide
  • Fahrenheit — water freezes at 32°F and boils at 212°F. Used primarily in the United States for everyday weather and cooking
  • The two scales meet at −40° — the only temperature that is the same in both Celsius and Fahrenheit
  • A change of 1°C equals a change of 1.8°F

When You Need to Convert Celsius to Fahrenheit

  • Travel to the US — US weather forecasts, thermostats and ovens all use Fahrenheit
  • Cooking American recipes — US recipes typically list oven temperatures in Fahrenheit
  • Medical contexts — US medical records and some older thermometers use Fahrenheit
  • Understanding international weather — comparing forecasts from different countries
  • Science and engineering — converting between units used in international publications

FAQs

Multiply the Celsius temperature by 9, divide by 5, then add 32. For example, 25°C × 9 ÷ 5 + 32 = 77°F.

37°C is 98.6°F — normal human body temperature.

100°C is 212°F — the boiling point of water at sea level.

0°C is 32°F — the freezing point of water.

Celsius and Fahrenheit are equal at −40°. This is the only temperature where both scales give the same reading.

The US adopted the Fahrenheit scale before the metric system became the international standard. Most other countries switched to Celsius as part of metrication, but the US retained Fahrenheit for everyday use.

Yes — completely free, no sign-up required.

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