Unit Converters

Temperature Converter

Convert Celsius, Fahrenheit, Kelvin, Rankine, and Réaumur.

Convert temperature values with clear unit labels, full-precision calculations, and a practical reference table.

Use the Temperature Converter

Enter a value, choose the units, and calculate. Your input stays in this browser.

How to use the Temperature Converter

  1. Enter the source value.
  2. Choose the source and destination measurement units or systems.
  3. Select Calculate and review the result, formula, and reference values.
  4. Use Swap where available to reverse the selected units.

Worked example

20 °C = 68 °F.

Assumptions and limitations

  • Values below absolute zero are rejected.
  • Temperature differences use different rules from absolute temperatures.

Frequently asked questions

How accurate is the Temperature Converter?

The calculator uses documented conversion constants and keeps normal browser numeric precision until display rounding.

Are my values stored?

No. The conversion runs in your browser and entered values are not saved.

Why can a converted value be approximate?

Some units depend on a convention or physical conditions. Any such assumption is stated beside the result.