📐 The Formula Explained

Celsius to Kelvin: K = °C + 273.15

Kelvin to Celsius: °C = K - 273.15

The conversion is simple because both scales use the same unit size. Kelvin starts at absolute zero (-273.15°C), the lowest possible temperature.

❓ Why 273.15?

The number 273.15 represents the difference between the zero points of the two scales:

• Celsius zero (0°C): The freezing point of water
• Kelvin zero (0 K): Absolute zero, where all molecular motion stops

Lord Kelvin proposed this scale in 1848 to create a temperature scale starting from absolute zero, making it ideal for scientific calculations.

🔬 When to Use Each Scale

Use Celsius when:

• Measuring everyday temperatures
• Weather forecasting
• Cooking and baking
• Medical thermometry

Use Kelvin when:

• Scientific research and calculations
• Physics and chemistry equations
• Thermodynamics
• Astronomical measurements

💡 Interesting Facts

• Kelvin is the SI base unit for temperature
• We write "0 K" not "0°K" (no degree symbol)
• Absolute zero (0 K) has never been reached, only approached
• The coldest natural place on Earth is about 184 K (-89°C)
• The surface of the Sun is approximately 5,778 K (5,505°C)

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1. Precision: Use the precision slider to control decimal places
2. Scientific Notation: Enter values like 3.5e2 for 350
3. Negative Values: Kelvin cannot be negative (minimum is 0 K)
4. Batch Mode: Process up to 1000 values at once
5. History: Access your last 10 conversions anytime

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