{
  "entity_type": "unit_conversion_page",
  "id": "mph-to-mach",
  "name": "Miles per hour to Mach (sea level)",
  "title": "Miles per hour to Mach (sea level) Converter (mph to mach)",
  "description": "Convert miles per hour to Mach (sea level): 1 mph = 0.00131369 mach. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.",
  "quantity": "speed",
  "quantity_name": "Speed",
  "base_unit": "m/s",
  "from_unit": {
    "symbol": "mph",
    "display": "mph",
    "name": "miles per hour",
    "singular": "mile per hour"
  },
  "to_unit": {
    "symbol": "mach",
    "display": "mach",
    "name": "Mach (sea level)",
    "singular": "Mach"
  },
  "linear": true,
  "factor": 0.001313687576,
  "inverse_factor": 761.2159986,
  "formula": "Mach (sea level) = miles per hour × 0.001313687576",
  "reverse_formula": "miles per hour = Mach (sea level) × 761.2159986",
  "unit_relation": "1 mph = 0.00131369 mach",
  "examples": [
    {
      "value": 5,
      "result": 0.00656844,
      "text": "5 mph = 0.00656844 mach"
    },
    {
      "value": 12.5,
      "result": 0.0164211,
      "text": "12.5 mph = 0.0164211 mach"
    },
    {
      "value": 100,
      "result": 0.131369,
      "text": "100 mph = 0.131369 mach"
    }
  ],
  "table": [
    {
      "mph": 1,
      "mach": 0.00131369
    },
    {
      "mph": 2,
      "mach": 0.00262738
    },
    {
      "mph": 3,
      "mach": 0.00394106
    },
    {
      "mph": 4,
      "mach": 0.00525475
    },
    {
      "mph": 5,
      "mach": 0.00656844
    },
    {
      "mph": 6,
      "mach": 0.00788213
    },
    {
      "mph": 7,
      "mach": 0.00919581
    },
    {
      "mph": 8,
      "mach": 0.0105095
    },
    {
      "mph": 9,
      "mach": 0.0118232
    },
    {
      "mph": 10,
      "mach": 0.0131369
    },
    {
      "mph": 15,
      "mach": 0.0197053
    },
    {
      "mph": 20,
      "mach": 0.0262738
    },
    {
      "mph": 25,
      "mach": 0.0328422
    },
    {
      "mph": 30,
      "mach": 0.0394106
    },
    {
      "mph": 40,
      "mach": 0.0525475
    },
    {
      "mph": 50,
      "mach": 0.0656844
    },
    {
      "mph": 75,
      "mach": 0.0985266
    },
    {
      "mph": 100,
      "mach": 0.131369
    },
    {
      "mph": 200,
      "mach": 0.262738
    },
    {
      "mph": 250,
      "mach": 0.328422
    },
    {
      "mph": 500,
      "mach": 0.656844
    },
    {
      "mph": 1000,
      "mach": 1.31369
    }
  ],
  "faq": [
    {
      "q": "How many Mach (sea level) are in one mile per hour?",
      "a": "1 mph = 0.00131369 mach. 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 miles per hour to Mach (sea level)?",
      "a": "Multiply the value in miles per hour by 0.001313687576: Mach (sea level) = miles per hour × 0.001313687576. For example, 5 mph = 0.00656844 mach."
    },
    {
      "q": "How do I convert Mach (sea level) back to miles per hour?",
      "a": "Multiply by the inverse factor 761.2159986 (miles per hour = Mach (sea level) × 761.2159986), or use the Mach (sea level)-to-miles per hour 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=mph&to_unit=mach",
    "calculator": "https://tttkmbb.com/api/v1/calculate/speed?value=5&from_unit=mph&to_unit=mach",
    "mcp_tool": "convert_units",
    "mcp_arguments": {
      "value": 5,
      "from_unit": "mph",
      "to_unit": "mach"
    }
  },
  "links": {
    "html": "https://tttkmbb.com/conversion/mph-to-mach",
    "markdown": "https://tttkmbb.com/conversion/mph-to-mach.md",
    "json": "https://tttkmbb.com/conversion/mph-to-mach.json",
    "reverse": "https://tttkmbb.com/conversion/mach-to-mph",
    "quantity_converter": "https://tttkmbb.com/conversion/speed",
    "units": "https://tttkmbb.com/api/v1/units?quantity=speed"
  },
  "timestamp": "2026-09-24"
}