{
  "id": "kelvin-to-celsius",
  "version": "6ed282004745",
  "status": "published",
  "name": "Kelvin to Celsius Converter",
  "question": "How do I convert kelvin to Celsius?",
  "summary": "Converts kelvins (K) to degrees Celsius (°C) and back, with the exact unit definitions.",
  "category": "convert",
  "subcategory": "temperature",
  "url": "https://www.acalculator.org/convert/kelvin-to-celsius",
  "markdown": "https://www.acalculator.org/convert/kelvin-to-celsius.md",
  "kind": "formulas",
  "method": "°C = K − 273.15",
  "assumptions": [
    "A kelvin and a degree Celsius are the same size; the scales differ only in their zero: 0 K is −273.15 °C.",
    "Nothing is colder than absolute zero (0 K, −273.15 °C, −459.67 °F), so a value below it gives no answer.",
    "Exact on the typed decimals: at most 6 decimal places (6 significant digits below 0.0001), rounded half up; an answer of 1 billion or more shows at most 15 significant digits."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "value": {
        "title": "Kelvins (K)",
        "description": "The amount in kelvins to convert.",
        "type": "number",
        "minimum": 0,
        "maximum": 1000000000000
      },
      "result": {
        "title": "Degrees Celsius (°C)",
        "description": "The same amount in degrees Celsius.",
        "type": "number",
        "minimum": -273.15,
        "maximum": 999999999726.85
      }
    }
  },
  "solve": {
    "fillAny": 1,
    "variables": [
      "value",
      "result"
    ],
    "inputsOnly": []
  },
  "outputs": {
    "value": {
      "label": "Kelvins (K)",
      "description": "The amount in kelvins to convert.",
      "format": "number"
    },
    "result": {
      "label": "Degrees Celsius (°C)",
      "description": "The amount in degrees Celsius.",
      "format": "number"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "value": 300
    },
    "outputs": {
      "result": 26.85
    },
    "text": "300 K = 26.85 °C."
  },
  "examples": [
    {
      "given": {
        "value": 0
      },
      "expect": {
        "result": -273.15
      },
      "source": "exact unit definitions in NIST SP 811 (2008), Appendix B.8"
    },
    {
      "given": {
        "value": 300
      },
      "expect": {
        "result": 26.85
      },
      "source": "exact unit definitions in NIST SP 811 (2008), Appendix B.8"
    },
    {
      "given": {
        "result": 26.85
      },
      "expect": {
        "value": 300
      },
      "source": "exact unit definitions in NIST SP 811 (2008), Appendix B.8"
    }
  ],
  "sources": [
    "NIST SP 811 (2008), Chapter 4, section 4.2.1.1: Celsius temperature t = T − T0 with T0 = 273.15 K; the degree Celsius is equal in size to the kelvin, retrieved 2026-10-18. https://www.nist.gov/pml/special-publication-811/nist-guide-si-chapter-4-two-classes-si-units-and-si-prefixes",
    "NIST SP 811 (2008), Guide for the Use of the International System of Units, Appendix B.8: Factors for Units Listed Alphabetically (bold factors are exact), retrieved 2026-10-18. https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8"
  ],
  "related": [
    "celsius-to-kelvin",
    "fahrenheit-to-celsius",
    "celsius-to-fahrenheit",
    "kelvin-to-fahrenheit"
  ],
  "changelog": []
}