{
  "slug": "free-fall",
  "title": "Free Fall Calculator",
  "heading": "Free Fall Distance & Speed Calculator",
  "category": "math",
  "url": "https://www.revenuelab.fyi/toolbox/free-fall",
  "summary": "Drop time, impact speed, and energy.",
  "description": "How fast is something moving after falling a given height, and how long does it take? Vacuum assumption — real drops slow down from drag.",
  "formula": "t = √(2h ÷ g); v = g × t",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=free-fall",
  "inputs": [
    {
      "id": "h",
      "label": "Drop height",
      "kind": "number",
      "hint": null,
      "default": 10,
      "unit": "m",
      "min": 0,
      "max": null
    },
    {
      "id": "mass",
      "label": "Mass",
      "kind": "number",
      "hint": null,
      "default": 1,
      "unit": "kg",
      "min": 0,
      "max": null
    },
    {
      "id": "g",
      "label": "Gravity",
      "kind": "number",
      "hint": null,
      "default": 9.81,
      "unit": "m/s²",
      "min": 0.1,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "time",
      "label": "Fall time (s)",
      "format": "decimal",
      "hint": null,
      "primary": true
    },
    {
      "id": "speed",
      "label": "Impact speed (m/s)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "kmh",
      "label": "Impact speed (km/h)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "energy",
      "label": "Kinetic energy (J)",
      "format": "decimal",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Drop height: 10 m",
      "Mass: 1 kg",
      "Gravity: 9.81 m/s²"
    ],
    "outputs": [
      "Fall time (s): 1.43",
      "Impact speed (m/s): 14.01",
      "Impact speed (km/h): 50.4",
      "Kinetic energy (J): 98.1"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter drop height (m).",
      "Enter mass (kg).",
      "Enter gravity (m/s²).",
      "Read your fall time (s) on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "h": 6,
        "mass": 0.6,
        "g": 5.886
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "h": 10,
        "mass": 1,
        "g": 9.81
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "h": 16,
        "mass": 1.6,
        "g": 15.696000000000002
      }
    }
  ],
  "limitations": [
    "Results are rounded for display; the underlying calculation keeps full precision.",
    "Very large or very small inputs may hit floating-point limits in the browser.",
    "Inputs outside the accepted range are clamped rather than rejected."
  ],
  "faq": [
    {
      "q": "How does the free fall distance & speed calculator work?",
      "a": "How fast is something moving after falling a given height, and how long does it take? Vacuum assumption — real drops slow down from drag. The underlying maths is: t = √(2h ÷ g); v = g × t"
    },
    {
      "q": "What do I need to enter?",
      "a": "3 values: drop height, mass, and gravity. Each field starts with a sensible default, so you can change one number at a time and watch the result move."
    },
    {
      "q": "What does the fall time (s) result mean?",
      "a": "It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds."
    },
    {
      "q": "Is this calculator free, and do I need an account?",
      "a": "Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser."
    },
    {
      "q": "How accurate is the result?",
      "a": "It applies the standard formula exactly, so the arithmetic is precise. Results are rounded for display; the underlying calculation keeps full precision."
    },
    {
      "q": "Who is this tool for?",
      "a": "It's built for students, developers, and anyone who needs the answer right now without setting up a spreadsheet."
    }
  ],
  "related": [],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Free Fall Calculator (https://www.revenuelab.fyi/toolbox/free-fall)"
}