Temperature Converter
Enter a temperature and see it instantly in Celsius, Fahrenheit and Kelvin.
✔ 100% Free✔ No Signup✔ No Watermark✔ Unlimited Use
Convert Temperature Between Every Scale
This free temperature converter shows a temperature in Celsius, Fahrenheit and Kelvin at the same time. Type a value, pick its scale, and read the other two instantly. It is the simplest way to convert Celsius to Fahrenheit, Fahrenheit to Celsius, or either to Kelvin.
The formulas are applied exactly and update as you type. Use it for weather, cooking, science homework, or any time two temperature scales meet.
How to Use the Temperature Converter
- 1Type your temperature in the box.
- 2Choose the scale you entered it in.
- 3Read the value in the other two scales, updated live.
Why Use MakeToolz's Temperature Converter?
Three scales
Celsius, Fahrenheit and Kelvin, all shown together.
See all at once
Enter one value and read the other scales instantly.
Exact formulas
Uses the standard conversion formulas, not rounded shortcuts.
Any direction
Start from any scale and convert to the others.
Private
All conversion runs in your browser.
Free
No signup, no limits.
How the Temperature Scales Relate
The three scales measure the same thing but start from different zero points and use different step sizes. Celsius sets 0 at the freezing point of water and 100 at its boiling point at sea level. Fahrenheit sets those same two points at 32 and 212, so its degrees are smaller and its zero sits lower. Kelvin uses the same step size as Celsius but starts at absolute zero, the coldest possible temperature, where all molecular motion stops.
Because the scales share physical reference points, converting between them is just arithmetic. To go from Celsius to Fahrenheit, multiply by 9/5 and add 32. To go from Fahrenheit to Celsius, subtract 32 and multiply by 5/9. To reach Kelvin from Celsius, add 273.15. The tool applies these formulas exactly, so a value entered in one scale is correct in the other two.
Who Uses a Temperature Converter
Travelers convert weather forecasts when they land in a country that uses the other scale. Cooks convert oven settings between Celsius and Fahrenheit so a recipe from abroad still works. Students and lab workers use Kelvin because science measures heat from absolute zero, which makes physics and chemistry formulas simpler. Nurses and parents check body temperature, where the line between normal and a fever is only a few degrees. In every case the reading is the same heat, just labeled by a different scale.
Key Temperature Points Across Scales
| Point | Celsius | Fahrenheit | Kelvin |
|---|---|---|---|
| Absolute zero | -273.15 | -459.67 | 0 |
| Water freezes | 0 | 32 | 273.15 |
| Room temperature | 22 | 71.6 | 295.15 |
| Body temperature | 37 | 98.6 | 310.15 |
| Water boils | 100 | 212 | 373.15 |
Benefits and Limits
The benefit is that you never have to remember three separate formulas or risk a sign error under pressure. Enter one number and read all three scales at once, done to full precision. That matters for an oven set wrong by 20 degrees or a fever misread by a couple of degrees.
One limit to keep in mind is that water boils at exactly 100 Celsius only at sea level. At high altitude the boiling point drops because air pressure is lower, so a recipe may behave differently in the mountains. The freezing point is far more stable. Also, Kelvin never uses a degree symbol or negative numbers, because its scale starts at the lowest temperature that can exist.
Common Mistakes and Tips
- Do not add 32 before multiplying when going from Celsius to Fahrenheit. The order is multiply by 1.8 first, then add 32. Reversing it gives a wrong answer.
- Remember that Fahrenheit degrees are smaller. A 10-degree change in Celsius is an 18-degree change in Fahrenheit, so the scales spread apart as temperatures rise.
- Do not write a degree symbol with Kelvin. It is written as 300 K, not 300 degrees K.
- Tip: minus 40 is the one point where Celsius and Fahrenheit read the same number, a handy check that your formula is working.
If you also convert distances or heights alongside temperatures, the length converter covers meters, feet, and miles. For quick sanity checks on percentages, the percentage calculator is nearby too.
People Also Ask
What is 100 degrees Fahrenheit in Celsius?
100 degrees Fahrenheit is about 37.8 Celsius. That is just above normal body temperature, which is why 100 F often signals a mild fever.
What is a normal body temperature in Fahrenheit?
The average is about 98.6 Fahrenheit, which equals 37 Celsius. A reading a degree or two higher usually points to a fever.
Why does science use Kelvin?
Kelvin starts at absolute zero, so it never uses negative numbers. That makes gas and energy formulas simpler and avoids sign errors in calculations.
At what temperature are Celsius and Fahrenheit equal?
At minus 40. Both scales read minus 40 at that exact point, which is a useful way to check a conversion.
How do I convert Celsius to Kelvin?
Add 273.15 to the Celsius value. So 25 Celsius is 298.15 Kelvin. Enter a value with Celsius selected to see it instantly.
What oven temperature is 180 Celsius in Fahrenheit?
180 Celsius is 356 Fahrenheit, often rounded to 350 on US ovens. This is a common baking temperature.
Does water always boil at 100 Celsius?
Only at sea level. At higher altitude the lower air pressure makes water boil below 100 Celsius, which can change cooking times.