Kelvin to Celsius Converter
Unit Converter
Instant · Precise · Universal
6 units available
6 categories total
How to Convert Kelvin to Celsius
To Celsius: °C = K − 273.15. To Fahrenheit: °F = (K − 273.15) × 9/5 + 32. To Rankine: °R = K × 9/5.
K = °C + 273.15. The kelvin scale starts at absolute zero (0 K = −273.15 °C). Same degree size as Celsius.
For example, 1 Kelvin (K) = -272.15 Celsius (°C).
Kelvin to Celsius — Common Values
| Kelvin (K) | Celsius (°C) |
|---|---|
| 0.1 | -273.05 |
| 0.5 | -272.65 |
| 1 | -272.15 |
| 2 | -271.15 |
| 5 | -268.15 |
| 10 | -263.15 |
| 25 | -248.15 |
| 50 | -223.15 |
| 100 | -173.15 |
| 500 | 226.85 |
| 1000 | 726.85 |
About Kelvin (K)
Definition
The kelvin is the SI base unit of thermodynamic temperature, defined by fixing the Boltzmann constant at exactly 1.380649 × 10⁻²³ J/K. Zero kelvin (0 K) is absolute zero.
Mathematical Relationship
K = °C + 273.15. The kelvin scale starts at absolute zero (0 K = −273.15 °C). Same degree size as Celsius.
Conversion Formula
To Celsius: °C = K − 273.15. To Fahrenheit: °F = (K − 273.15) × 9/5 + 32. To Rankine: °R = K × 9/5.
Practical Applications
Color temperature of lights (e.g., 2700 K warm white, 6500 K daylight), cryogenics, and engineering thermodynamics.
Interesting Facts
The cosmic microwave background radiation has a temperature of 2.725 K. The surface of the Sun is about 5,778 K. Absolute zero has never been fully reached.
Common Mistakes
Writing '°K' instead of 'K' — kelvin never uses a degree sign. Also, confusing 0 K with 0 °C.
Educational Tips
Kelvin = Celsius + 273.15. There are no negative kelvins (in classical physics). Absolute zero (0 K) is the theoretical minimum temperature.
About Celsius (°C)
Definition
The degree Celsius is a unit of temperature on the Celsius scale, where 0 °C is the freezing point and 100 °C is the boiling point of water at standard atmospheric pressure.
Mathematical Relationship
°C = K − 273.15. The Celsius and Kelvin scales have identical degree sizes — they differ only by an offset of 273.15.
Conversion Formula
To Fahrenheit: °F = °C × 9/5 + 32. To Kelvin: K = °C + 273.15. To Rankine: °R = (°C + 273.15) × 9/5.
Practical Applications
Weather reports, cooking temperatures, body temperature (37 °C normal), refrigerator settings (2–4 °C), and industrial processes.
Interesting Facts
−40 °C = −40 °F — the only point where Celsius and Fahrenheit scales intersect. The hottest recorded temperature on Earth was 56.7 °C in Death Valley.
Common Mistakes
Forgetting the °C × 9/5 + 32 offset when converting to Fahrenheit. Also, assuming 0 °C = 0 K (actually 0 °C = 273.15 K).
Educational Tips
Key anchors: 0 °C = water freezes, 37 °C = body temp, 100 °C = water boils. For quick °C→°F: double and add 30 (approximate).