Formula
Degrees Celsius = kelvin − 273.15. The size of one kelvin is the same as one degree Celsius, so a ± kelvin uncertainty carries across as the same ± °C uncertainty.
Kelvin to Celsius Calculator
Convert kelvin to degrees Celsius with the exact 273.15 offset, optional measurement uncertainty and a printable science or lab worksheet record.
Worked example
For 300 K, Celsius = 300 − 273.15 = 26.85 °C. If the thermometer uncertainty is ±0.2 K, the converted record is 26.85 °C ±0.2 °C before any reporting-rounding policy is applied.
Professional note
Master’s Tip: do not write “degrees Kelvin.” The SI unit name is kelvin, symbol K, while Celsius temperatures are written with degrees Celsius, symbol °C.
Regional and unit assumptions
Standard or basis: SI temperature-scale conversion using the exact relation t/°C = T/K − 273.15. This is a measurement and worksheet calculator, not a calibration certificate or safety ruling.
Assumptions and limitations
- The kelvin input is treated as thermodynamic temperature on the SI kelvin scale.
- The calculator clamps negative kelvin values to zero because temperatures below 0 K are outside ordinary thermodynamic temperature conversion.
- The conversion offset is exact: 0 °C equals 273.15 K.
- Measurement uncertainty is optional and is reported with the same numerical size in °C because kelvin and Celsius increments are equal.
- For calibrated laboratory, safety, medical, food, industrial or compliance work, use the instrument certificate, required rounding rule and official procedure.
Methodology & Accuracy
How this calculator is checked
CalculationTime pages are built around visible arithmetic: the formula, assumptions, worked example and practical limitations are shown so the result can be checked rather than simply trusted.
Formula used
Degrees Celsius = kelvin − 273.15. The size of one kelvin is the same as one degree Celsius, so a ± kelvin uncertainty carries across as the same ± °C uncertainty.
Standard or basis
Standard or basis: SI temperature-scale conversion using the exact relation t/°C = T/K − 273.15. This is a measurement and worksheet calculator, not a calibration certificate or safety ruling.
Where a calculator follows a named legal, trade or industry standard, that standard is cited visibly. Otherwise the page uses transparent general arithmetic and states its limits.Master's Tip
Master’s Tip: do not write “degrees Kelvin.” The SI unit name is kelvin, symbol K, while Celsius temperatures are written with degrees Celsius, symbol °C.
Related calculators
Questions
How do I convert kelvin to Celsius?
Subtract 273.15 from the kelvin temperature. For example, 300 K − 273.15 = 26.85 °C.
What is 0 K in Celsius?
0 K is −273.15 °C. This is absolute zero on the kelvin scale.
Is one kelvin the same size as one degree Celsius?
Yes. Kelvin and Celsius have the same interval size; only the zero point is different.
Can kelvin be negative?
For ordinary thermodynamic temperature conversion, kelvin is not below 0 K. This calculator clamps the input at zero for practical records.
What should I print for a kelvin-to-Celsius worksheet?
Print the kelvin input, Celsius result, exact formula, rounding increment, uncertainty if used, date, page URL and notes area for the source instrument or classroom problem.
Calculation note
Kelvin and Celsius are linked by an exact offset, not a multiplier. That makes the conversion simple, but the printed record still needs to say which scale was measured and which rounding rule was used.
Kelvin starts at absolute zero
The kelvin scale is an SI temperature scale whose zero point is absolute zero. Celsius uses the same interval size but places zero at the freezing-point reference used historically for water-based temperature work.
The offset is exact
The practical conversion is a fixed subtraction: Celsius equals kelvin minus 273.15. Because the interval size is the same, a difference of 1 K is also a difference of 1 °C.
Uncertainty belongs beside the answer
A sensor reading such as 300.0 K is not automatically more precise than the instrument. Keeping uncertainty and rounding on the printed report stops the conversion from implying false accuracy.