Convert Celsius to Fahrenheit (and Kelvin)
Temperature converter: °C to °F and back, plus Kelvin. Instant, no sign-up, in the browser.
Formula: °F = °C × 9/5 + 32. The reverse is °C = (°F − 32) × 5/9. Kelvin is °C + 273.15. Pick Temperature, then the pair.
Weather apps in the US show Fahrenheit; science and most of Europe use Celsius. Kelvin is for physics notes, not a weather widget.
The same converter also handles length and weight. Stay in Temperature so you do not mix km with °C. Huge values hit an overflow error.
The line is F = C × 9/5 + 32. Water freezes at 0 °C and 32 °F, boils at 100 °C and 212 °F. Minus 40 is the same number on both scales. A fever of 38 °C is 100.4 °F. Kelvin is Celsius plus 273.15, so 0 K is −273.15 °C and there is no degree sign in the symbol. This page opens on Celsius to Fahrenheit. Body temperature and an oven are both this formula; only the expected range changes.
FAQ
Is Kelvin in the list?
Yes, under Temperature.
Why 9/5?
The Fahrenheit degree is 5/9 of a Celsius degree. The +32 offset is the ice point on the Fahrenheit scale.
Does rounding match a lab?
Display rounding is for everyday use. For lab work keep more decimals in your own sheet.