Conversion guide
Celsius to Fahrenheit: formula and temperature table
Convert weather, room, cooking, and technical temperatures from Celsius to Fahrenheit. Unlike proportional unit conversions, temperature scales require both multiplication and an offset.
Formulas in both directions
°F = (°C × 9/5) + 32°C = (°F − 32) × 5/9The scale ratio is exactly 9/5 and the Fahrenheit zero point creates a 32-degree offset. Therefore a simple multiplier alone cannot convert the readings.
Common conversion values
| degree Celsius (°C) | degree Fahrenheit (°F) |
|---|---|
| -40 °C | -40 °F |
| -20 °C | -4 °F |
| -10 °C | 14 °F |
| 0 °C | 32 °F |
| 5 °C | 41 °F |
| 10 °C | 50 °F |
| 20 °C | 68 °F |
| 25 °C | 77 °F |
| 30 °C | 86 °F |
| 37 °C | 98.6 °F |
| 40 °C | 104 °F |
| 100 °C | 212 °F |
Worked real-world examples
Example 1
A thermostat is set to 18 °C. Convert the setting for a Fahrenheit-only controller.
(18 × 9/5) + 32 = 64.418 °C = 64.4 °FExample 2
A recipe specifies an oven temperature of 200 °C. Convert it for an oven marked in Fahrenheit.
(200 × 9/5) + 32 = 392200 °C = 392 °FWhat the units mean
degree Celsius (°C)
The degree Celsius uses the same interval size as the kelvin. At standard atmospheric pressure, water freezes near 0 °C and boils near 100 °C.
degree Fahrenheit (°F)
The degree Fahrenheit is a temperature interval used mainly in the United States. Water freezes at 32 °F and boils near 212 °F at standard pressure.
Where these units are used
Celsius is used for everyday weather and temperature measurement in most countries and for scientific reporting alongside kelvin. Fahrenheit remains the everyday scale in the United States and a few territories.
Important distinctions
A temperature reading and a temperature difference convert differently. For a difference, 1 °C equals 1.8 °F and no 32-degree offset is added. This page converts temperature readings.
Accuracy and rounding
Weather is commonly rounded to a whole degree, while cooking may use 5- or 10-degree settings. Laboratory work should retain the measurement uncertainty and avoid implying more precision than the sensor provides.
Frequently asked questions
Why do I add 32 when converting Celsius?
The two scales have different zero points. The +32 aligns 0 °C with 32 °F after the interval size is adjusted.
At what temperature are Celsius and Fahrenheit equal?
They show the same numeric reading at −40 degrees.
Is doubling Celsius a good Fahrenheit estimate?
For everyday positive temperatures, doubling and adding 30 is a rough mental estimate, not an exact method.
Does the formula change for negative temperatures?
No. The same linear formula applies to negative and positive readings.