Convert Celsius to Kelvin
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Science
Real-World Reference Values
| Value | Kelvin | |
|---|---|---|
| 0 °C | 273.15 K | Freezing point of water |
| -273.15 °C | 0 K | Absolute zero — coldest possible temperature |
| 100 °C | 373.15 K | Boiling point of water at sea level |
| 25 °C | 298.15 K | Standard ambient temperature in chemistry (SATP) |
Common Uses
- Scientific calculations requiring absolute temperature scale
- Chemistry lab work where reaction rates depend on Kelvin values
- Physics problems involving gas laws (PV = nRT uses Kelvin)
Practical Tips
Quick Conversions
| Unit Name | Symbol | Per 1 Celsius |
|---|---|---|
| Celsius | °C | 1 |
| Delisle | °De | 148.5 |
| Fahrenheit | °F | 33.8 |
| Kelvin | K | 274.15 |
| Newton | °N | 0.33 |
| Rankine | °R | 493.47 |
| Réaumur | °Ré | 0.8 |
Frequently Asked Questions
Why is 0 K equal to −273.15 °C and not a round number?
Absolute zero is fixed by physics, not by definition. It is the temperature at which classical thermal motion stops, and the Celsius scale was already in use when the Kelvin was anchored to it. Lord Kelvin's 1848 proposal set absolute zero at the limit measured from real gas behavior, which fell at −273.15 °C when rounded to two decimals. The 2019 SI redefinition fixed the Boltzmann constant exactly, so the offset 273.15 is now baked into the official definition of the kelvin itself.
How do I convert Celsius to Kelvin?
To convert Celsius to Kelvin, use the conversion where 1 Celsius (°C) = 274.15 Kelvin (K). For example, 1 Celsius = 274.15 Kelvin.
What are common Celsius to Kelvin conversions?
Here are common conversions: 1 Celsius = 274.15 Kelvin, 5 Celsius = 278.15 Kelvin, 10 Celsius = 283.15 Kelvin, 25 Celsius = 298.15 Kelvin, 50 Celsius = 323.15 Kelvin, 100 Celsius = 373.15 Kelvin.
When would I need to convert Celsius to Kelvin?
Scientific calculations requiring absolute temperature scale. Chemistry lab work where reaction rates depend on Kelvin values. Physics problems involving gas laws (PV = nRT uses Kelvin).
How precise are the conversions?
All conversions use exact factors verified against NIST and ISO standards with up to 10 significant figures of precision. Results are calculated using IEEE 754 double-precision arithmetic, which provides approximately 15-17 significant digits. For temperature and other non-linear conversions, exact formulas are used rather than approximations.
How many Kelvin is 0 Celsius? (Freezing point of water)
0 Celsius equals 273.15 K Kelvin. This is a frequently referenced value because it represents freezing point of water.
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Conversions keep full numeric precision through the calculation and round only the displayed result.
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