{
  "entity_type": "unit_conversion_page",
  "id": "light-years-to-km",
  "name": "Light-years to Kilometers",
  "title": "Light-years to Kilometers Converter (ly to km)",
  "description": "Convert light-years to kilometers: 1 ly = 9460730000000 km. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.",
  "quantity": "length",
  "quantity_name": "Length",
  "base_unit": "m",
  "from_unit": {
    "symbol": "ly",
    "display": "ly",
    "name": "light-years",
    "singular": "light-year"
  },
  "to_unit": {
    "symbol": "km",
    "display": "km",
    "name": "kilometers",
    "singular": "kilometer"
  },
  "linear": true,
  "factor": 9460730473000,
  "inverse_factor": 1.057000834e-13,
  "formula": "kilometers = light-years × 9460730473000",
  "reverse_formula": "light-years = kilometers × 1.057000834e-13",
  "unit_relation": "1 ly = 9460730000000 km",
  "examples": [
    {
      "value": 5,
      "result": 47303700000000,
      "text": "5 ly = 47303700000000 km"
    },
    {
      "value": 12.5,
      "result": 118259000000000,
      "text": "12.5 ly = 118259000000000 km"
    },
    {
      "value": 100,
      "result": 946073000000000,
      "text": "100 ly = 946073000000000 km"
    }
  ],
  "table": [
    {
      "ly": 1,
      "km": 9460730000000
    },
    {
      "ly": 2,
      "km": 18921500000000
    },
    {
      "ly": 3,
      "km": 28382200000000
    },
    {
      "ly": 4,
      "km": 37842900000000
    },
    {
      "ly": 5,
      "km": 47303700000000
    },
    {
      "ly": 6,
      "km": 56764400000000
    },
    {
      "ly": 7,
      "km": 66225100000000
    },
    {
      "ly": 8,
      "km": 75685800000000
    },
    {
      "ly": 9,
      "km": 85146600000000
    },
    {
      "ly": 10,
      "km": 94607300000000
    },
    {
      "ly": 15,
      "km": 141911000000000
    },
    {
      "ly": 20,
      "km": 189215000000000
    },
    {
      "ly": 25,
      "km": 236518000000000
    },
    {
      "ly": 30,
      "km": 283822000000000
    },
    {
      "ly": 40,
      "km": 378429000000000
    },
    {
      "ly": 50,
      "km": 473037000000000
    },
    {
      "ly": 75,
      "km": 709555000000000
    },
    {
      "ly": 100,
      "km": 946073000000000
    },
    {
      "ly": 200,
      "km": 1892150000000000
    },
    {
      "ly": 250,
      "km": 2365180000000000
    },
    {
      "ly": 500,
      "km": 4730370000000000
    },
    {
      "ly": 1000,
      "km": 9460730000000000
    }
  ],
  "faq": [
    {
      "q": "How many kilometers are in one light-year?",
      "a": "1 ly = 9460730000000 km. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures."
    },
    {
      "q": "What is the formula to convert light-years to kilometers?",
      "a": "Multiply the value in light-years by 9460730473000: kilometers = light-years × 9460730473000. For example, 5 ly = 47303700000000 km."
    },
    {
      "q": "How do I convert kilometers back to light-years?",
      "a": "Multiply by the inverse factor 1.057000834e-13 (light-years = kilometers × 1.057000834e-13), or use the kilometers-to-light-years page."
    }
  ],
  "sources": [
    {
      "name": "NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors",
      "url": "https://www.nist.gov/pml/special-publication-811",
      "type": "standard",
      "retrieved_at": "2026-09-24"
    },
    {
      "name": "BIPM – The International System of Units (SI Brochure, 9th edition)",
      "url": "https://www.bipm.org/en/publications/si-brochure",
      "type": "standard",
      "retrieved_at": "2026-09-24"
    },
    {
      "name": "Wikipedia – Conversion of units",
      "url": "https://en.wikipedia.org/wiki/Conversion_of_units",
      "type": "reference",
      "retrieved_at": "2026-09-24"
    }
  ],
  "freshness": {
    "type": "static",
    "max_age_seconds": null,
    "note": "Fixed conversion factors (NIST/BIPM definitions); results never go stale."
  },
  "api": {
    "convert": "https://tttkmbb.com/api/v1/convert?value=5&from_unit=ly&to_unit=km",
    "calculator": "https://tttkmbb.com/api/v1/calculate/length?value=5&from_unit=ly&to_unit=km",
    "mcp_tool": "convert_units",
    "mcp_arguments": {
      "value": 5,
      "from_unit": "ly",
      "to_unit": "km"
    }
  },
  "links": {
    "html": "https://tttkmbb.com/conversion/light-years-to-km",
    "markdown": "https://tttkmbb.com/conversion/light-years-to-km.md",
    "json": "https://tttkmbb.com/conversion/light-years-to-km.json",
    "reverse": "https://tttkmbb.com/conversion/km-to-light-years",
    "quantity_converter": "https://tttkmbb.com/conversion/length",
    "units": "https://tttkmbb.com/api/v1/units?quantity=length"
  },
  "timestamp": "2026-09-24"
}