Cernarus

Convert Kelvin to Celsius – Temperature Converter

This converter converts a temperature given in kelvins (K) to the equivalent temperature in degrees Celsius (°C). The mathematical relationship between the two units is fixed and linear, so the conversion is deterministic for any numerical input.

While the conversion formula is exact, practical temperature values originate from measurements that have uncertainty and depend on the measurement method, calibration, and environmental conditions. Consult calibration and traceability guidance when using converted values for compliance, safety, or high-accuracy engineering work.

Updated Nov 11, 2025

Interactive Converter

Convert between kelvin and celsius with precision rounding.

Quick reference table

KelvinCelsius
1 K-272.15 °C
5 K-268.15 °C
10 K-263.15 °C
25 K-248.15 °C
50 K-223.15 °C
100 K-173.15 °C

Methodology

Kelvin is the SI base unit for thermodynamic temperature. Celsius is a derived scale offset from Kelvin. The conversion is performed by subtracting a fixed offset: Celsius equals Kelvin minus 273.15.

The numerical conversion itself is exact and not approximated. Measurement-related uncertainty comes from instruments and procedures. For laboratory and regulatory contexts, follow recognized standards for temperature measurement and calibration such as the International Temperature Scale (ITS-90) and laboratory accreditation standards.

For safety or regulatory use (for example workplace heat guidance), verify sensor calibration, measurement placement, and applicable thresholds in the relevant standards or legal guidance rather than relying solely on a single converted reading.

Worked examples

0 K → 0 − 273.15 = −273.15 °C (absolute zero in Celsius)

273.15 K → 273.15 − 273.15 = 0 °C (freezing point of pure water at standard pressure)

310.15 K → 310.15 − 273.15 = 37 °C (approximate human body temperature)

Key takeaways

Subtract 273.15 from a kelvin temperature to get degrees Celsius. The arithmetic conversion is exact; measurement uncertainty depends on instruments and procedures.

For calibrated, regulatory, or safety-critical applications, pair this numerical conversion with appropriate calibration records, uncertainty estimates, and adherence to relevant standards.

Further resources

Expert Q&A

Is the Kelvin to Celsius conversion exact?

Yes. The conversion uses a fixed offset: Celsius equals Kelvin minus 273.15. The mathematical operation is exact; any numerical rounding is an output formatting decision.

Why do measured temperatures still have uncertainty after conversion?

The conversion is a simple arithmetic offset, but measured temperatures come from instruments that have accuracy limits, drift, and environmental influences. Calibration, measurement technique, and instrument uncertainty determine the overall confidence in the converted value.

How should I handle rounding and significant figures?

Choose rounding based on measurement precision and context. For scientific work, match the number of significant figures to the instrument's uncertainty. For everyday use, one or two decimal places is typically sufficient.

Do I need to calibrate sensors before using this converter for compliance or safety?

Yes. For compliance, safety, clinical, or legal applications, use calibrated sensors with traceable calibration certificates and follow applicable standards and workplace regulations before relying on measurements and conversions.

Is absolute zero the same in Kelvin and Celsius?

Absolute zero equals 0 K, which converts to −273.15 °C using the standard offset.

Sources & citations