Celsius to Kelvin Converter
Enter the value that you want to convert Celsius (°C) to kelvin (K) or kelvin to Celsius.Also written as °C to K conversion.
1 Celsius = 274.1500000 kelvin
Formula: K = °C + 273.15
°C to K — Celsius to kelvin
10 Celsius = 283.15000 kelvin
Popular Temperature Converters:
Temperature Scale Comparison Chart
Celsius to Kelvin in Science & Engineering
Every chemistry and physics calculation involving the ideal gas law (PV=nRT), thermodynamic efficiency, or energy calculations requires temperature in Kelvin. Converting is simple (K = °C + 273.15) but forgetting it is a common source of errors in student labs and engineering calculations. Cryogenics, semiconductor manufacturing, and space science all work primarily in Kelvin.
Why Convert Celsius to Kelvin?
Understanding the Celsius
The Celsius scale was proposed by Swedish astronomer Anders Celsius in 1742, originally with 0° as the boiling point and 100° as freezing — later inverted.
Celsius (°C) is the most widely used temperature scale globally, adopted by every country except the United States for everyday use. It sets water's freezing point at 0°C and boiling point at 100°C at standard atmospheric pressure. The scale is used in weather forecasts, cooking, medicine (normal body temperature ≈ 37°C), scientific research, and industrial processes worldwide. Since 1954, it has been defined relative to the Kelvin scale: °C = K − 273.15.
The Kelvin Explained
The Kelvin scale begins at absolute zero (−273.15°C) — the theoretical lowest possible temperature where all molecular motion ceases.
Kelvin (K) is the SI base unit of temperature, essential in physics, chemistry, and engineering. It uses the same increment size as Celsius but starts at absolute zero. Key values: 0 K = absolute zero, 273.15 K = water freezes, 373.15 K = water boils. Kelvin is required for gas law calculations (PV=nRT), thermodynamic efficiency, color temperature in photography/lighting (5500K = daylight), and cryogenic engineering.
Temperature Scales in Context
Temperature conversion is one of the few non-linear unit conversions people encounter daily. Celsius dominates scientific work and most countries, Fahrenheit remains standard in the US for weather and cooking, Kelvin is required in thermodynamics and gas law calculations, and Rankine appears in some US engineering applications. Converting between these scales requires formulas rather than simple multiplication.
Celsius to kelvin metric conversion table
| 0.01 °C | = | 273.16000 K |
| 0.1 °C | = | 273.25000 K |
| 1 °C | = | 274.15000 K |
| 2 °C | = | 275.15000 K |
| 3 °C | = | 276.15000 K |
| 4 °C | = | 277.15000 K |
| 5 °C | = | 278.15000 K |
| 6 °C | = | 279.15000 K |
| 7 °C | = | 280.15000 K |
| 8 °C | = | 281.15000 K |
| 9 °C | = | 282.15000 K |
| 10 °C | = | 283.15000 K |
| 11 °C | = | 284.15000 K |
| 12 °C | = | 285.15000 K |
| 13 °C | = | 286.15000 K |
| 14 °C | = | 287.15000 K |
| 15 °C | = | 288.15000 K |
| 16 °C | = | 289.15000 K |
| 17 °C | = | 290.15000 K |
| 18 °C | = | 291.15000 K |
| 19 °C | = | 292.15000 K |
| 20 °C | = | 293.15000 K |
| 30 °C | = | 303.15000 K |
| 40 °C | = | 313.15000 K |
| 50 °C | = | 323.15000 K |
| 60 °C | = | 333.15000 K |
| 70 °C | = | 343.15000 K |
| 80 °C | = | 353.15000 K |
| 90 °C | = | 363.15000 K |
| 100 °C | = | 373.15000 K |
| 200 °C | = | 473.15000 K |
| 300 °C | = | 573.15000 K |
| 400 °C | = | 673.15000 K |
| 500 °C | = | 773.15000 K |
| 600 °C | = | 873.15000 K |
| 700 °C | = | 973.15000 K |
| 800 °C | = | 1073.15000 K |
| 900 °C | = | 1173.15000 K |
| 1000 °C | = | 1273.15000 K |
How to Convert °C to K (Celsius to Kelvin)?
We can convert Celsius to kelvin by using an example.
Example:
Convert 20 Celsius to Kelvin?
We know 1 Celsius = 274.1500000 kelvin; 1 Kelvin = -272.1500000 Celsius.
20 Celsius = ___K
20 × 274.1500000 = 293.15000 K (we know 1 Celsius = 274.1500000 kelvin)
Answer:
20 Celsius = 293.15000 kelvin
How to Convert Celsius to Kelvin
The Kelvin scale is an absolute temperature scale used in science. It starts at absolute zero (the coldest possible temperature) and uses the same degree size as Celsius. Converting between them is simply a matter of adding or subtracting 273.15.
- Write down the temperature in Celsius (°C).
- Add 273.15 to the Celsius value.
- The result is the temperature in Kelvin (K).
- Note: Kelvin does not use the degree symbol — it is written as K, not °K.
Important Celsius to Kelvin Values in Science
Key temperatures used in physics, chemistry, and cryogenics:
| Celsius | Kelvin |
|---|---|
| −273.15 °C | 0 K |
| −196 °C | 77 K |
| −78.5 °C | 194.65 K |
| 0 °C | 273.15 K |
| 20 °C | 293.15 K |
| 25 °C | 298.15 K |
| 100 °C | 373.15 K |
Solved Examples: Celsius to Kelvin
Question 1: Room temperature is 22 °C. Express this in Kelvin.
Solution:
Formula: K = °C + 273.15
K = 22 + 273.15
Answer: 22 °C = 295.15 K
Question 2: Liquid nitrogen boils at −196 °C. What is this in Kelvin?
Solution:
K = °C + 273.15
K = −196 + 273.15
K = 77.15
Answer: −196 °C = 77.15 K
Question 3: A chemical reaction occurs at 350 °C. Convert to Kelvin.
Solution:
K = 350 + 273.15
K = 623.15
Answer: 350 °C = 623.15 K
Question 4: Convert absolute zero (−273.15 °C) to Kelvin.
Solution:
K = −273.15 + 273.15
K = 0
Answer: −273.15 °C = 0 K (the lowest possible temperature)
Question 5: Standard temperature for gas law calculations is 0 °C. What is it in Kelvin?
Solution:
K = 0 + 273.15
Answer: 0 °C = 273.15 K
Practice Problems
Try solving these on your own to test your understanding:
- Convert 37 °C (body temperature) to Kelvin. (Answer: 310.15 K)
- What is −40 °C in Kelvin? (Answer: 233.15 K)
- Convert 1000 °C (molten lava) to Kelvin. (Answer: 1273.15 K)
- The cosmic microwave background is about −270 °C. Convert to K. (Answer: 3.15 K)
- Convert 25 °C to Kelvin. (Answer: 298.15 K)
- What is −100 °C in Kelvin? (Answer: 173.15 K)
Why Science Uses the Kelvin Scale
Many physical laws (ideal gas law PV = nRT, Stefan-Boltzmann law, blackbody radiation) require an absolute temperature scale. Using Celsius or Fahrenheit in these equations would produce incorrect results because they have arbitrary zero points. Kelvin places zero at the point where molecular motion reaches its theoretical minimum, making temperature ratios physically meaningful.
Absolute Zero: The Coldest Possible Temperature
Absolute zero (0 K = −273.15 °C) is a fundamental limit in physics. At this temperature, particles have the lowest possible energy (though quantum mechanics dictates they cannot be completely motionless). Scientists have cooled atoms to within billionths of a kelvin of absolute zero in laboratories, but reaching exactly 0 K is considered impossible according to the third law of thermodynamics.
Kelvin in Cryogenics and Superconductivity
Cryogenic engineering regularly works in Kelvin. Liquid helium boils at 4.2 K, superconducting magnets in MRI machines operate below 10 K, and quantum computers require temperatures near 15 millikelvin (0.015 K). Understanding the Celsius-to-Kelvin conversion is essential for anyone working with low-temperature physics or cryogenic systems.
Key Takeaways
- Formula: K = °C + 273.15.
- Kelvin and Celsius degrees are the same size; only the zero point differs.
- Kelvin has no negative values — 0 K is absolute zero.
- Standard temperature in chemistry (STP) is 273.15 K (0 °C).
- Do not write °K — the correct notation is just K.
- The Kelvin scale is required for thermodynamic calculations.
Celsius to Kelvin Conversion Formula
K = °C + 273.15
1 Celsius = 274.1500000 kelvin
1 kelvin = -272.1500000 Celsius
Frequently Asked Questions
How many kelvin are in 1 Celsius?
1 Celsius equals 274.15000 kelvin. Note: Temperature conversion uses a formula, not simple multiplication.
How do I convert Celsius to kelvin?
Use the conversion formula shown above. For example, 278.15 kelvin equals 5 Celsius. Temperature scales have different zero points, so a formula (not simple multiplication) is required.
How do I convert kelvin to Celsius?
Use the reverse formula. 1 kelvin equals -272.15000 Celsius. See the formula section above for the exact equation.
What is 10 Celsius in kelvin?
10 Celsius is equal to 283.15000 kelvin.
What is 100 Celsius in kelvin?
100 Celsius is equal to 373.15000 kelvin.