Celsius to Fahrenheit Converter
Convert Celsius (°C) to Fahrenheit (°F) with a precise formula, quick temperature presets, and an easy-to-follow calculation breakdown.
Convert your temperature
Enter any Celsius value or choose a common reference below.
Fahrenheit result
Converted temperature—Enter a Celsius temperature to see the Fahrenheit equivalent.
How to convert Celsius to Fahrenheit
The Celsius and Fahrenheit scales use different zero points and degree sizes. To convert Celsius to Fahrenheit, multiply the Celsius value by 9/5 (or 1.8), then add 32.
Worked example: 25°C
Therefore, 25 degrees Celsius is equal to 77 degrees Fahrenheit.
This same formula works for positive, negative, and decimal temperatures.
Celsius to Fahrenheit conversion chart
Use these familiar temperature points for a quick comparison.
| Celsius | Fahrenheit | Reference |
|---|---|---|
| −40°C | −40°F | Scales intersect |
| 0°C | 32°F | Water freezes* |
| 10°C | 50°F | Cool weather |
| 20°C | 68°F | Common indoor reference |
| 25°C | 77°F | Warm weather |
| 30°C | 86°F | Hot weather |
| 37°C | 98.6°F | Temperature conversion reference |
| 100°C | 212°F | Water boils* |
*Water reference temperatures are approximate and depend on pressure and conditions; boiling is shown at standard atmospheric pressure.
Understanding Celsius and Fahrenheit
Commonly used internationally for weather, science and everyday temperature readings.
Used widely for weather and household temperatures in the United States.
The offset aligns the two scales at water’s freezing reference: 0°C = 32°F.
Why is the multiplier 9/5?
Between the usual freezing and boiling reference points of water, the Celsius scale spans 100 degrees while Fahrenheit spans 180 degrees. Their interval ratio is 180/100 = 9/5.
When is this conversion useful?
Temperature conversion helps when comparing international weather forecasts, adjusting recipes, reading appliance specifications, following classroom exercises and interpreting travel information.
Accuracy and decimal temperatures
The tool applies the standard mathematical relationship between the two temperature scales. It accepts negative numbers and decimals, and formats results to a practical number of digits. Display rounding may occur for long decimal results.
For scientific, medical, or industrial applications, follow the precision and measurement standards required for your work. A unit conversion does not verify the accuracy of the original temperature measurement.
Frequently asked questions
What is the Celsius to Fahrenheit formula?
Multiply the Celsius temperature by 9/5 and add 32: °F = (°C × 9/5) + 32.
How much is 0°C in Fahrenheit?
0°C equals 32°F.
What is 20°C in Fahrenheit?
20°C equals 68°F.
What is 25°C in Fahrenheit?
25°C equals 77°F.
At what temperature are both scales equal?
−40°C equals −40°F.
Can I enter negative or decimal values?
Yes. The calculator accepts both negative temperatures and decimals.
Does the tool work on a phone?
Yes. The converter adapts to mobile and desktop screens.
Is the converter free?
Yes. No account is required to perform a conversion.