Temperature Converter
Quickly convert temperatures between Celsius, Fahrenheit, and Kelvin while seeing all three scales at once.
Frequently asked questions
What’s the difference between Celsius, Fahrenheit, and Kelvin?
Celsius and Fahrenheit are common everyday scales, while Kelvin is an absolute scale used in science. Kelvin starts at absolute zero and has no negative values in physical reality.
Can Kelvin be negative?
No. 0 K is absolute zero, the theoretical lowest temperature. If you enter values that would imply negative Kelvin, double-check the input or scale.
What formulas are used for conversion?
Common formulas are: `F = C * 9/5 + 32`, `C = (F - 32) * 5/9`, and `K = C + 273.15`. The converter applies these consistently.
Why is 32°F equal to 0°C?
Fahrenheit uses a different zero point and degree size. The 32°F offset is part of how the scale was originally defined.
Simple inputs
Pick the scale you know, enter the temperature, and choose the scale you need. The converter keeps everything in sync behind the scenes.
Always see every scale
Even when you target a single scale, the calculator shows Celsius, Fahrenheit, and Kelvin equivalents so you can compare or reuse the number instantly.
Perfect for science and travel
Use it for lab work, cooking, travel planning, or weather comparisons—any time you need to jump between temperature systems.
Temperature conversion: Celsius, Fahrenheit, Kelvin
Temperature scales measure the same physical concept, but they use different zero points and step sizes.
The three common scales
- Celsius (°C): water freezes at 0°C and boils at 100°C (at normal atmospheric pressure).
- Fahrenheit (°F): water freezes at 32°F and boils at 212°F.
- Kelvin (K): an absolute scale used in science. 0 K is absolute zero.
Quick conversion formulas
F = C * 9/5 + 32C = (F - 32) * 5/9K = C + 273.15
Common questions
- Why is 32°F equal to 0°C? Fahrenheit uses a different reference point.
- Can Kelvin be negative? No. Kelvin starts at absolute zero.
How to use the converter
- Choose the input scale.
- Enter the temperature value.
- Read the converted values in the other scales.
If you’re converting for cooking or weather, rounding to one decimal is usually enough. For scientific work, keep more decimals.
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