Kelvin to Celsius Converter

°C

Common Conversions

K	°C
0	-273.15
77.15	-196
195.15	-78
233.15	-40
273.15	0
293.15	20
298.15	25
310.15	37
373.15	100
473.15	200
773.15	500
1273.15	1000

Why this conversion matters in chemistry

Kelvin is the unit chemistry calculations live in — gas laws, rate constants, equilibrium expressions all want absolute temperature. But nobody sets a thermostat or writes a bench protocol in Kelvin. Converting 548 K to 275°C turns a thermogravimetric decomposition onset into a number you can actually set on an oven. The arithmetic is subtracting 273.15 — trivial, but always worth doing before the result enters a final report. The size of the degree is identical on both scales, which means temperature differences (ΔT) are the same in K as in °C; only the absolute value needs adjusting.

Formula

°C = K − 273.15

Worked Examples

298.15 K = 25°C

Thermodynamic standard state. Almost every tabulated ΔG° or ΔH° you'll reference is given at this temperature.

273.15 K = 0°C

Water's freezing point — and the STP reference temperature for classical gas-law calculations.

373.15 K = 100°C

Water's normal boiling point at 1 atm. The other pillar of the Celsius scale.

77 K = −196.15°C

Liquid nitrogen boiling point. A useful cryogen anchor — this is the temperature you reach when something goes into a dewar of LN₂.

Frequently Asked Questions

How do you convert Kelvin to Celsius?

Subtract 273.15. So 373.15 K is 100°C, 298.15 K is 25°C. The degree has the same size on both scales — only the zero point shifts, which is why the conversion is a simple subtraction rather than a scaling.

When would I need to go this direction?

Almost always at the end of a calculation. Gas-law and kinetics math runs in Kelvin, but reports, protocols, and lab setpoints live in Celsius. A rate constant computed at 323 K corresponds to a protocol step at 50°C — the Celsius number is what you'd actually write in a procedure.

What's 0 Kelvin in Celsius?

−273.15°C. Absolute zero — the theoretical floor where classical thermal motion stops. Nothing colder is physically achievable, though the third law of thermodynamics says you can approach it asymptotically but never quite reach it.