Celsius ↔ Fahrenheit
Type in one box. The other updates. Formula: °F = °C × 9/5 + 32.
How to use the Celsius ↔ Fahrenheit
What does the Celsius ↔ Fahrenheit do?
Convert Celsius to Fahrenheit and back; It applies this page-specific rule: convert Celsius to Fahrenheit and back.
Which inputs does this calculator use?
To convert celsius to fahrenheit and back, enter Celsius, Fahrenheit; keep every value in the same example; the page then updates the result from the current values; Start with a familiar case covered by this rule - The conversion formula multiplies Celsius by 9/5 and adds 32 for Fahrenheit; the reverse subtracts 32 and multiplies by 5/9 - so the expected result can confirm the settings.
How should the calculator result be read?
For a result intended to convert celsius to fahrenheit and back, the conversion formula multiplies Celsius by 9/5 and adds 32 for Fahrenheit; the reverse subtracts 32 and multiplies by 5/9; read fahrenheit together with the original celsius rather than as an isolated answer, and confirm that its units or structure match the intended use.
Can I type into either box?
When the goal is to convert celsius to fahrenheit and back, yes.
What are useful reference points?
When using the page to convert celsius to fahrenheit and back, water freezes at 0 degrees Celsius or 32 degrees Fahrenheit under standard conditions.
Limits and accuracy
When using this calculator to convert celsius to fahrenheit and back, temperature-scale conversion does not account for measurement uncertainty, sensor calibration, or different oven and weather conditions; check the entered values, units, rounding, and assumptions before using the answer for an important decision; keep celsius until the output has been checked in its intended destination. For a repeatable check when you need to convert celsius to fahrenheit and back, record Celsius alongside the final output and selected options. A known example using celsius can confirm how the page will convert celsius to fahrenheit and back.
How this works
The two common everyday temperature scales share a linear map: multiply Celsius by 9/5 and add 32 to get Fahrenheit. The inverse subtracts 32 and multiplies by 5/9.
Fixed points people actually remember: 0 °C = 32 °F (ice), 37 °C ≈ 98.6 °F (oral body temperature as usually quoted), 100 °C = 212 °F (water at standard pressure), 180 °C ≈ 356 °F (a common oven setting).
Fan-assisted ovens are not a different temperature scale. Cookbooks often tell you to drop a conventional Celsius setting by about 20 °C when using fan. That is a cooking rule, not this formula.
Frequently asked questions
Boiling point?
100 °C = 212 °F at standard pressure.
Body temperature?
37 °C ≈ 98.6 °F.
Negative values?
Yes. −40 is the same on both scales.