1. How to convert Kelvin to Celsius
Kelvin and Celsius do not share a zero point, so the conversion needs an
offset as well as a ratio: °C = K − 273.15. That is an affine conversion, not a
proportional one.
Worked at the two values people ask for most: 1 K = -272.15 °C and
300 K = 26.85 °C. Going the other way, K = °C + 273.15, so
1 °C = 274.15 K — a direction with its own page, Celsius to Kelvin.
Results are given to eight significant figures. That is more precision than most jobs need — for a rough figure, treat 1 K as about -272.15 °C and adjust — but rounding early and multiplying afterwards is how a small error becomes a visible one, so the full figure is what the converter carries.
2. Kelvin to Celsius conversion table
| Kelvin (K) | Celsius (°C) |
|---|---|
| 0 K | -273.15 °C |
| 100 K | -173.15 °C |
| 200 K | -73.15 °C |
| 273.15 K | 0 °C |
| 293.15 K | 20 °C |
| 300 K | 26.85 °C |
| 310.15 K | 37 °C |
| 373.15 K | 100 °C |
Every row is the same factor applied — nothing in the table is a special case, and any value in between behaves the same way. Type your own figure into the converter above and the Formula tile shows the arithmetic being used, so the result is checkable rather than taken on trust.
3. What the two units are
- Kelvin (K). Kelvin starts at absolute zero and uses the Celsius degree, so 0 K is −273.15 °C.
- Celsius (°C). Celsius puts water’s freezing point at 0 and its boiling point at 100 at standard pressure.
Both scales are converted through kelvin internally, which is why the arithmetic handles negative values correctly — an offset applied in the wrong order is the usual source of a wrong answer here.
Temperature is the one category that needs an offset as well as a factor, because the scales do not share a zero. That has a consequence people trip over constantly: you cannot convert a temperature difference the same way you convert a temperature. A room at 20 °C is 68 °F, but a rise of 20 °C is a rise of 36 °F. For an interval, apply the 9/5 ratio and drop the offset.
If the pair you actually want is not this one, the full unit converter runs every 4 temperature units off the same factor table, along with 11 other categories of measurement.
4. Kelvin to Celsius FAQs
How do I convert Kelvin to Celsius?
Apply K − 273.15 — the scales need an offset as well as a ratio because they do not share a zero. 1 K = -272.15 °C, and 300 K = 26.85 °C.
What is 1 K in °C?
1 K = -272.15 °C. The full formula is °C = K − 273.15, and 1 °C = 274.15 K going the other way.
What is 300 K in °C?
300 K = 26.85 °C. The table above works the same factor through 8 values, and the converter takes any figure you type — including decimals and negatives.
How do I convert Celsius to Kelvin?
K = °C + 273.15, so 1 °C = 274.15 K. Use the Swap button in the converter to reverse the direction without retyping the value, or open the dedicated Celsius to Kelvin page.
Can I convert a temperature difference the same way?
No. The offset belongs to a point on the scale, not to an interval. A room at 20 °C is 68 °F, but a rise of 20 °C is a rise of 36 °F — for a difference you apply the 9/5 ratio and drop the +32. It is the most common temperature-conversion error in engineering copy.
Is anything I type sent to a server?
No. The factor table ships with the page and every conversion runs in your browser. Nothing is uploaded, logged or written to storage, and the converter keeps working offline once the page has loaded.