What is it?
The Temperature Converter changes temperatures between Celsius, Fahrenheit, Kelvin, Rankine and Réaumur, and adds a quick note on whether a body temperature is a fever.
Who is it for?
Parents checking a child’s temperature from a Fahrenheit thermometer, travellers reading weather abroad, cooks with foreign oven settings, and science students.
How to use it
- Type the Value and pick the From unit.
- Every other unit is shown under In every unit; tap a value to copy it, or use Copy result.
- Tap ⇅ Swap to convert the other way.
Quick formulas
- °F = °C × 1.8 + 32. Quick estimate: double the °C and add 30.
- °C = (°F − 32) ÷ 1.8.
- K = °C + 273.15. Kelvin has no degree sign and no negative values.
Body temperature
- Normal is about 36.1–37.2 °C (97–99 °F). It is lower in the morning and higher in the evening.
- 38 °C (100.4 °F) or above is a fever. Readings under the arm are about 0.5 °C lower than in the mouth.
- See a doctor for fever in babies under 3 months, fever above 39.4 °C (103 °F), or fever lasting more than 3 days. This tool is not medical advice.
Good to know
Water boils at 100 °C (212 °F) only at sea level. In hill areas it boils at a lower temperature; the Elevation Finder shows the boiling point for any place.
Errors and how to fix them
- Kelvin below zero: impossible; check the unit.
- A result looks hugely wrong: check the From unit. Picking a unit that looks similar to the one you meant is the most common mistake.
- Very long decimals: results show up to 10 significant digits; round to what you need.
Open the tool: Temperature Converter
Still stuck?
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Questions, or an error not listed here?
Tell us in the comments: what you were doing, the exact message you saw, and your device and browser. We read every comment and add new fixes to this article.