Celsius is a temperature scale with water freezing at 0 C and boiling at 100 C.
Celsius to Fahrenheit Converter — C to F
Convert Celsius (C) to Fahrenheit (F) using the exact temperature formula. See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Celsius to Fahrenheit converter
Converter
Temperature Converter
Convert Celsius, Fahrenheit, Kelvin, Rankine, Delisle, Newton, Reaumur, and Romer.
Context values
Some unit families need one extra value for a physically accurate result.
Fahrenheit is a temperature scale with water freezing at 32 F and boiling at 212 F.
Convert the source temperature to Kelvin, then convert Kelvin to the target scale.
Temperature conversion uses Kelvin as the intermediate absolute scale.
Reserved above the conversion cards and below the converter.
About Converting Celsius to Fahrenheit
Celsius and Fahrenheit are the two everyday temperature scales, and converting between them matters for reading weather forecasts, following recipes, and understanding scientific data across regions. Celsius is typically associated with standard temperature scale in nearly every country except the United States, while Fahrenheit is typically associated with united States (primary everyday temperature scale).
Formula
°F = (°C × 9/5) + 32
Celsius and Fahrenheit both offset from a common zero point, so the conversion needs a multiply and an addition rather than a single multiplication factor. The formula scales the 100-degree Celsius span onto Fahrenheit's 180-degree span, then shifts it so 0 °C lands on 32 °F.
Simple example
(0 × 9/5) + 32 = 32 °F
0 celsius = 32 fahrenheit. 0 °C converts to 32 °F, the freezing point of water at standard atmospheric pressure.
Real-world example
(0 × 9/5) + 32 = 32 °F
0 celsius = 32 fahrenheit. 0 °C converts to 32 °F, the freezing point of water at standard atmospheric pressure.
Conversion table
| Celsius (C) | Fahrenheit (F) |
|---|---|
| -40 C | -40 F |
| -20 C | -4 F |
| 0 C | 32 F |
| 20 C | 68 F |
| 37 C | 98.6 F |
| 100 C | 212 F |
Reverse conversion: Fahrenheit to Celsius
(33.8 − 32) × 5/9 = 1 °C
33.8 fahrenheit = 1 celsius.
°C = (°F − 32) × 5/9
For a page dedicated to this direction, see Fahrenheit to Celsius.
Celsius vs. Fahrenheit
| Aspect | Celsius | Fahrenheit |
|---|---|---|
| Family | SI-derived temperature scale | Non-SI temperature scale |
| Typical use | Weather forecasting and climate reporting worldwide | Everyday weather reporting and thermostats in the US |
| Where it's used | Standard temperature scale in nearly every country except the United States | United States (primary everyday temperature scale) |
Understanding the Celsius
Celsius (C) measures temperature. Celsius is defined relative to the Kelvin scale, with 0 °C set at 273.15 K. It is classified as a SI-derived temperature scale.
Where it's used: Standard temperature scale in nearly every country except the United States
Uses of the Celsius today
- Weather forecasting and climate reporting worldwide
- Scientific and laboratory temperature measurement (alongside Kelvin)
- Cooking and food safety in most countries outside the US
History of the Celsius
Swedish astronomer Anders Celsius proposed a 100-point temperature scale in 1742, but his original scale ran in the opposite direction, with 0° at water's boiling point and 100° at freezing.
The scale was reversed to its modern orientation shortly after his death, commonly attributed to instrument maker Daniel Ekström and naturalist Carl Linnaeus around 1744-1745.
The scale was renamed from 'centigrade' to 'Celsius' by international agreement in 1948, and it is now formally defined as the Kelvin scale shifted by 273.15, rather than independently by the freezing and boiling points of water.
Historical origin. Celsius was not the invention of a single named person; it developed through the process described above.
Understanding the Fahrenheit
Fahrenheit (F) measures temperature. Fahrenheit sets water's freezing point at 32 °F and boiling point at 212 °F at standard atmospheric pressure. It is classified as a Non-SI temperature scale.
Where it's used: United States (primary everyday temperature scale) A small number of other territories, e.g. the Bahamas, Belize, Cayman Islands, Liberia, Palau
Uses of the Fahrenheit today
- Everyday weather reporting and thermostats in the US
- Cooking temperatures in US recipes
- Some US industrial and HVAC contexts
History of the Fahrenheit
German physicist Daniel Gabriel Fahrenheit developed the scale around 1724, originally basing 0° on the coldest temperature he could reliably reproduce with an ice-salt mixture, and calibrating other points using human body temperature and the freezing point of water.
The modern Fahrenheit scale was later standardized so that water freezes at exactly 32 °F and boils at exactly 212 °F at one standard atmosphere, giving 180 degrees between the two reference points.
Historical origin. Fahrenheit was not the invention of a single named person; it developed through the process described above.
Celsius — sources
- BIPM SI Brochure — Celsius temperature scale — Formal definition tying Celsius to Kelvin.
Fahrenheit — sources
- NIST — Temperature scales overview — History and modern definitions of Fahrenheit and Celsius.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many fahrenheit are in 1 celsius?
1 celsius equals 33.8 fahrenheit, using the offset temperature formula rather than an estimate.
How do I convert celsius to fahrenheit?
Use the formula shown above: it involves both a multiplication and an addition/subtraction because the two scales don't share a common zero point.
How do I convert fahrenheit back to celsius?
Use the reverse factor: 1 fahrenheit equals -17.22222222 celsius. You can also use the swap control in the converter above to flip the direction instantly.
What is a celsius?
Celsius (C) measures temperature. Celsius is defined relative to the Kelvin scale, with 0 °C set at 273.15 K. It is classified as a SI-derived temperature scale.
What is a fahrenheit?
Fahrenheit (F) measures temperature. Fahrenheit sets water's freezing point at 32 °F and boiling point at 212 °F at standard atmospheric pressure. It is classified as a Non-SI temperature scale.
Is the Celsius to Fahrenheit conversion exact?
Yes. Both scales are formally defined relative to the Kelvin scale, so the conversion formula is exact — the only rounding involved is in how many decimal places you choose to display.
Where is the celsius still used today?
Standard temperature scale in nearly every country except the United States