# Degrees Celsius to degrees Fahrenheit converter

> Convert degrees Celsius to degrees Fahrenheit (Celsius to Fahrenheit) with the exact formula, a conversion chart and worked steps.

Interactive version: https://www.calcopenly.com/conversion/celsius-to-fahrenheit
Subject: Unit converters

A Celsius reading may describe weather, a room or an oven setting. Temperature scales use different zero points, so a ratio alone is insufficient. Converting a temperature reading is also different from converting a temperature difference, where the offset cancels.

Degrees Celsius and degrees Fahrenheit are not related by a single multiplier because the two scales start from different zero points, so the conversion uses a formula. 37 °C is 98.6 °F.

The Celsius and kelvin scales have the same step size; a Fahrenheit degree is 5/9 of a Celsius degree. Absolute zero is 0 K, −273.15 °C or −459.67 °F, and inputs below it are rejected.

## Inputs

- **Degrees Celsius (°C)**

## Results

- Degrees Fahrenheit (°F) — main result
- Conversion
- 1 °F in degrees Celsius (°C)

## Formula

$$
{}^\circ F = {}^\circ C \times \tfrac{9}{5} + 32
$$

## Worked examples

### 37 °C to °F

- Degrees Celsius (°C): 37 °C
- **Degrees Fahrenheit: 98.6 °F**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 15 °C to °F

- Degrees Celsius (°C): 15 °C
- **Degrees Fahrenheit: 59 °F**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

### 180 °C to °F

- Degrees Celsius (°C): 180 °C
- **Degrees Fahrenheit: 356 °F**
- Checked against: Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions)

## Questions

### When would I convert Celsius to Fahrenheit?

A Celsius reading may describe weather, a room or an oven setting. Temperature scales use different zero points, so a ratio alone is insufficient. Converting a temperature reading is also different from converting a temperature difference, where the offset cancels.

### What is the formula to convert Celsius to Fahrenheit?

Multiply by 9/5 (1.8) and add 32: 37 °C × 1.8 + 32 = 98.6 °F. The 1.8 is the ratio of degree sizes and the 32 is the offset between the two zero points.

### Is there a quick way to convert Celsius to Fahrenheit in your head?

Double the Celsius value and add 30. It is exact at 10 °C (50 °F) and drifts by 1 °F for every 5 °C away from 10: at 20 °C it gives 70 °F instead of 68 °F, and at 30 °C it gives 90 °F instead of 86 °F.

### What is 37 °C in Fahrenheit?

Exactly 98.6 °F: 37 × 1.8 + 32 = 98.6. 37 °C is the traditional figure for normal human body temperature, from Carl Wunderlich's 1868 study.

### How accurate is the degrees Celsius to degrees Fahrenheit converter?

Accuracy depends on your inputs and the method's assumptions. Decimal arithmetic uses 50 significant digits, but estimates, numerical methods and source data can be less precise; the displayed rounding does not remove those limits. It is checked against 3 worked examples whose answers come from independent sources; for example, “37 °C to °F” is checked against Exact-fraction computation from the legal unit definitions (scripts/gen-pairs.py, Python fractions).

### Where does the method come from?

NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B; NIST Handbook 44, Appendix C: General tables of units of measurement; BIPM, The International System of Units (SI Brochure), 9th edition.

## Sources

- [NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44, Appendix C: General tables of units of measurement](https://www.nist.gov/pml/weights-and-measures/publications/nist-handbooks/handbook-44)
- [BIPM, The International System of Units (SI Brochure), 9th edition](https://www.bipm.org/en/publications/si-brochure)