Everyday & industry
Temperature Converter
Convert temperatures between Celsius, Fahrenheit, Kelvin and Rankine, with a single conversion or a multi-scale table.
Enter a temperature, choose the source scale, and convert it instantly to another common temperature scale.
Temperature conversion uses fixed mathematical formulas and does not require external data.
Results update as you edit. Calculations run locally in your browser; your inputs are not saved.
Choose your temperature scales.
Calculated locally · Temperature Converter
Your Temperature Conversion
The converted value represents the same temperature expressed on a different scale.
Result Detail
Conversion Breakdown
Calculations pass through the unrounded Kelvin value. Decimal Places affects display only.
About this calculator
Quick conversion references
These are static reference relationships, not results calculated from your inputs.
- 0 °C = 32 °F.
- 100 °C = 212 °F.
- -40 °C = -40 °F.
- 0 °C = 273.15 K.
- 0 K = -273.15 °C.
- 0 K = -459.67 °F.
Temperature scales and precision
The converter transforms the source value to Kelvin, then converts from that same unrounded Kelvin value. Display rounding never feeds back into the calculation.
- Auto uses up to two decimal places for ordinary results and adds precision near absolute zero when rounding would hide the difference.
- Celsius and Fahrenheit use degree intervals with different zero points. Kelvin and Rankine are absolute scales whose zero is absolute zero.
- Rankine uses the same degree interval as Fahrenheit, starting at 0 °R at absolute zero.
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply the Celsius temperature by 9/5, then add 32. For example, 0 °C = 32 °F.
How do I convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit temperature, then multiply by 5/9. For example, 32 °F = 0 °C.
How do I convert Celsius to Kelvin?
Add 273.15 to the Celsius temperature. For example, 0 °C = 273.15 K.
What is absolute zero?
Absolute zero is 0 K, equal to -273.15 °C, -459.67 °F and 0 °R.
Why is -40 the same in Celsius and Fahrenheit?
The Celsius-to-Fahrenheit formula gives (-40 × 9/5) + 32 = -40, so both scales read -40 at that temperature.
What is Rankine?
Rankine is an absolute temperature scale with the same degree size as Fahrenheit. Its zero is absolute zero: 0 °R = 0 K.
This is a mathematical temperature-scale converter only. It does not provide weather, medical or cooking guidance.