Enter a temperature in Celsius, Fahrenheit or Kelvin and see it on all three scales at once. Useful for foreign recipes and ovens, weather from US sources, and science homework. Unlike length or weight, temperature scales don’t share a zero point, so the conversion is a formula rather than a simple factor — handled correctly here.
On all scales
- Celsius (°C)1 °C
- Fahrenheit (°F)33.8 °F
- Kelvin (K)274.15 K
How it works
The tool converts everything through Celsius as a common base. Fahrenheit relates to Celsius by °C = (°F − 32) × 5⁄9, and Kelvin by K = °C + 273.15. Because Fahrenheit and Celsius have different zero points and different degree sizes, you can’t just multiply by a factor the way you would for metres or grams — the offset matters.
That’s why 0 °C is 32 °F, not 0 °F, and why the two scales only meet at −40°, where −40 °C equals −40 °F. Kelvin shares the size of a Celsius degree but starts at absolute zero, so it’s just Celsius shifted by 273.15.
Practical examples
A recipe in Fahrenheit
An American recipe says bake at 350 °F. That’s about 176.7 °C — set the oven to 175–180 °C. Enter 350, from Fahrenheit, and read Celsius.
Body temperature
A fever of 38.5 °C reads as 101.3 °F on a US thermometer. Converting both ways helps when the device or the advice uses the other scale.
Weather from a US site
A forecast of 75 °F is a pleasant 23.9 °C. For a quick mental estimate, subtract 30 from the Fahrenheit figure and halve it — the tool gives the exact number.
Frequently asked questions
How do I convert Celsius to Fahrenheit?
Multiply by 9⁄5 (1.8) and add 32. So 20 °C × 1.8 = 36, plus 32 = 68 °F. The tool does this exactly; the “×2 and add 30” shortcut is only a rough approximation.
How do I convert Fahrenheit to Celsius?
Subtract 32, then multiply by 5⁄9. For 68 °F: 68 − 32 = 36, × 5⁄9 = 20 °C. Enter the Fahrenheit value and read the Celsius row for the precise result.
Why can’t I just use a conversion factor like with metres?
Because the scales have different zero points. Length and weight units share zero, so one factor works. Celsius and Fahrenheit don’t — 0° isn’t the same temperature on each — so the conversion needs both a multiply and an offset.
At what temperature do Celsius and Fahrenheit match?
At −40°: −40 °C equals −40 °F. It’s the single point where the two scales cross, a handy fact for checking that a conversion tool is doing the offset correctly.
What is Kelvin and when do I need it?
Kelvin starts at absolute zero (−273.15 °C), the coldest possible temperature, and uses the same degree size as Celsius. It’s standard in science; 0 °C is 273.15 K and room temperature (~25 °C) is about 298 K.
Can I enter negative temperatures?
Yes. Negatives work on every scale — for example −5 °C is 23 °F. Kelvin can’t physically go below 0, but the tool will still compute a value if you enter one.
Does it accept decimals and the Serbian comma?
Yes. Type 36,6 or 36.6 for body temperature — both are read as the same value. Results are shown to a sensible number of decimals.
Are the values I enter kept private?
Yes. The conversion runs entirely in your browser; nothing is uploaded and analytics never sees the numbers.
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