{
  "entity_type": "unit_conversion_page",
  "id": "calories-to-joules",
  "name": "Calories (small, thermochemical) to Joules",
  "title": "Calories (small, thermochemical) to Joules Converter (cal to J)",
  "description": "Convert calories (small, thermochemical) to joules: 1 cal = 4.184 J. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.",
  "quantity": "energy",
  "quantity_name": "Energy",
  "base_unit": "J",
  "from_unit": {
    "symbol": "cal",
    "display": "cal",
    "name": "calories (small, thermochemical)",
    "singular": "calorie"
  },
  "to_unit": {
    "symbol": "J",
    "display": "J",
    "name": "joules",
    "singular": "joule"
  },
  "linear": true,
  "factor": 4.184,
  "inverse_factor": 0.2390057361,
  "formula": "joules = calories (small, thermochemical) × 4.184",
  "reverse_formula": "calories (small, thermochemical) = joules × 0.2390057361",
  "unit_relation": "1 cal = 4.184 J",
  "examples": [
    {
      "value": 5,
      "result": 20.92,
      "text": "5 cal = 20.92 J"
    },
    {
      "value": 12.5,
      "result": 52.3,
      "text": "12.5 cal = 52.3 J"
    },
    {
      "value": 100,
      "result": 418.4,
      "text": "100 cal = 418.4 J"
    }
  ],
  "table": [
    {
      "cal": 1,
      "J": 4.184
    },
    {
      "cal": 2,
      "J": 8.368
    },
    {
      "cal": 3,
      "J": 12.552
    },
    {
      "cal": 4,
      "J": 16.736
    },
    {
      "cal": 5,
      "J": 20.92
    },
    {
      "cal": 6,
      "J": 25.104
    },
    {
      "cal": 7,
      "J": 29.288
    },
    {
      "cal": 8,
      "J": 33.472
    },
    {
      "cal": 9,
      "J": 37.656
    },
    {
      "cal": 10,
      "J": 41.84
    },
    {
      "cal": 15,
      "J": 62.76
    },
    {
      "cal": 20,
      "J": 83.68
    },
    {
      "cal": 25,
      "J": 104.6
    },
    {
      "cal": 30,
      "J": 125.52
    },
    {
      "cal": 40,
      "J": 167.36
    },
    {
      "cal": 50,
      "J": 209.2
    },
    {
      "cal": 75,
      "J": 313.8
    },
    {
      "cal": 100,
      "J": 418.4
    },
    {
      "cal": 200,
      "J": 836.8
    },
    {
      "cal": 250,
      "J": 1046
    },
    {
      "cal": 500,
      "J": 2092
    },
    {
      "cal": 1000,
      "J": 4184
    }
  ],
  "faq": [
    {
      "q": "How many joules are in one calorie?",
      "a": "1 cal = 4.184 J. 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 calories (small, thermochemical) to joules?",
      "a": "Multiply the value in calories (small, thermochemical) by 4.184: joules = calories (small, thermochemical) × 4.184. For example, 5 cal = 20.92 J."
    },
    {
      "q": "How do I convert joules back to calories (small, thermochemical)?",
      "a": "Multiply by the inverse factor 0.2390057361 (calories (small, thermochemical) = joules × 0.2390057361), or use the joules-to-calories (small, thermochemical) 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=cal&to_unit=J",
    "calculator": "https://tttkmbb.com/api/v1/calculate/energy?value=5&from_unit=cal&to_unit=J",
    "mcp_tool": "convert_units",
    "mcp_arguments": {
      "value": 5,
      "from_unit": "cal",
      "to_unit": "J"
    }
  },
  "links": {
    "html": "https://tttkmbb.com/conversion/calories-to-joules",
    "markdown": "https://tttkmbb.com/conversion/calories-to-joules.md",
    "json": "https://tttkmbb.com/conversion/calories-to-joules.json",
    "reverse": "https://tttkmbb.com/conversion/joules-to-calories",
    "quantity_converter": "https://tttkmbb.com/conversion/energy",
    "units": "https://tttkmbb.com/api/v1/units?quantity=energy"
  },
  "timestamp": "2026-09-24"
}