Temperature Converter
Convert a temperature between Celsius, Fahrenheit, Kelvin, and the other supported units in the temperature group. Unlike simple factor conversions, temperature scales use both a scale and an offset. Calculations run locally and can be copied with selected precision.
Runs locally — files stay on your deviceHow do you convert Celsius to Fahrenheit?
Multiply Celsius by 9/5 and add 32.
Formula: °F = °C × 9/5 + 32
Temperature scales use affine conversions
Celsius and Fahrenheit have different degree sizes and different zero points. The direct formula is °F = °C × 9/5 + 32; the reverse is °C = (°F − 32) × 5/9. Kelvin shares the Celsius degree size but uses absolute zero as its origin.
How it works
The unit engine converts the source value to a common base and then to the destination scale, applying offsets before or after factors in the correct order.
When to use it
- Convert a weather forecast.
- Translate an oven setting.
- Check laboratory values across scale conventions.
When not to use it
- Do not apply a simple multiplication without the offset.
- Do not report more precision than the measurement supports.
- Do not confuse temperature differences with absolute temperatures.
Worked examples
Freezing water
- Input
0 °C- Expected output
32 °F
The Fahrenheit offset is included.
Boiling reference
- Input
100 °C- Expected output
212 °F
At standard pressure this is the familiar boiling point reference.
Absolute scale
- Input
0 °C- Expected output
273.15 K
Kelvin uses the same interval size as Celsius.
Common mistakes
Forgetting +32
Celsius to Fahrenheit is not factor-only. Correction: Use °F = °C × 9/5 + 32.
Writing a degree symbol for Kelvin
The SI unit name is kelvin, symbol K. Correction: Write 273.15 K, not °K.
Overstating precision
A converted display cannot improve the original measurement. Correction: Choose precision appropriate to the source.
Limitations and privacy
- Floating-point results are rounded to the chosen display precision.
- Physical reference points vary with conditions such as pressure.
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Frequently asked questions
What is the Celsius to Fahrenheit formula?
Multiply Celsius by 9/5, then add 32.
Why is temperature not a factor-only conversion?
The scales have different zero points as well as different interval sizes.
Can I swap source and destination?
Yes, the converter provides a swap action.
Is Kelvin written with a degree sign?
No. Use K without a degree symbol.