{
  "id": "audiobook-length",
  "version": "87abc839efcf",
  "status": "published",
  "name": "Audiobook Length Calculator",
  "question": "How long will this audiobook take?",
  "summary": "Computes how long an audiobook takes to hear at a playback speed, the time saved, and how many days it takes at a daily listening time, from its length or from a word count.",
  "category": "everyday-life",
  "url": "https://www.acalculator.org/everyday-life/audiobook-length-calculator",
  "markdown": "https://www.acalculator.org/everyday-life/audiobook-length-calculator.md",
  "kind": "function",
  "method": "listening time = length ÷ speed; length from words = words ÷ 9,300 an hour; days = ⌈listening minutes ÷ minutes a day⌉",
  "assumptions": [
    "A word count becomes a length at 9,300 words per finished hour, the average ACX gives for narrators. Narrators differ.",
    "Times are shown to the nearest second (a half second rounds up). Time saved or added is the difference of the two rounded times.",
    "Days to finish round up, so the last day may be short."
  ],
  "inputs": {
    "$schema": "https://json-schema.org/draft/2020-12/schema",
    "type": "object",
    "properties": {
      "know": {
        "title": "I know",
        "description": "The length of the audiobook, or the number of words in the book.",
        "type": "string",
        "enum": [
          "length",
          "words"
        ]
      },
      "h": {
        "title": "Hours",
        "description": "The hours part of the audiobook’s length at normal speed.",
        "type": "integer",
        "minimum": 0,
        "maximum": 1000
      },
      "m": {
        "title": "Minutes",
        "description": "The minutes part of the audiobook’s length at normal speed.",
        "type": "integer",
        "minimum": 0,
        "maximum": 59
      },
      "words": {
        "title": "Words",
        "description": "The number of words in the book.",
        "type": "integer",
        "minimum": 1,
        "maximum": 10000000
      },
      "speed": {
        "title": "Playback speed",
        "description": "The speed you listen at, such as 1.5 for 1.5×.",
        "type": "number",
        "minimum": 0.25,
        "maximum": 4
      },
      "daily": {
        "title": "Minutes a day",
        "description": "How many minutes you listen each day. Leave empty to skip the days.",
        "type": "integer",
        "minimum": 1,
        "maximum": 1440
      }
    }
  },
  "outputs": {
    "listening": {
      "label": "Listening time",
      "description": "The length at normal speed ÷ the playback speed.",
      "format": "duration"
    },
    "saved": {
      "label": "Time saved",
      "description": "The length at normal speed minus the listening time, when you listen faster than 1×.",
      "format": "duration"
    },
    "added": {
      "label": "Time added",
      "description": "The listening time minus the length at normal speed, when you listen slower than 1×.",
      "format": "duration"
    },
    "length": {
      "label": "Length at 1×",
      "description": "The length at normal speed, given or worked out from the words at 9,300 words an hour.",
      "format": "duration"
    },
    "days": {
      "label": "Days to finish",
      "description": "The listening time in minutes ÷ the minutes a day, rounded up to whole days.",
      "format": "integer"
    }
  },
  "defaultAnswer": {
    "inputs": {
      "know": "length",
      "h": 11,
      "m": 30,
      "words": 90000,
      "speed": 1.5,
      "daily": 45
    },
    "outputs": {
      "listening": {
        "hours": 7,
        "minutes": 40,
        "seconds": 0
      },
      "saved": {
        "hours": 3,
        "minutes": 50,
        "seconds": 0
      },
      "length": {
        "hours": 11,
        "minutes": 30,
        "seconds": 0
      },
      "days": 11
    },
    "text": "At 1.5× the audiobook takes 7 hours, 40 minutes."
  },
  "examples": [
    {
      "given": {
        "know": "length",
        "h": 11,
        "m": 30,
        "speed": 1.5,
        "daily": 45
      },
      "expect": {
        "listening": {
          "hours": 7,
          "minutes": 40,
          "seconds": 0
        },
        "saved": {
          "hours": 3,
          "minutes": 50,
          "seconds": 0
        },
        "days": 11
      },
      "source": "hand calculation in content.mdx: 11.5 h ÷ 1.5 = 7 h 40 min; 11 h 30 min − 7 h 40 min = 3 h 50 min; 460 ÷ 45 = 10.2, so 11 days"
    },
    {
      "given": {
        "know": "words",
        "words": 93000,
        "speed": 1
      },
      "expect": {
        "length": {
          "hours": 10,
          "minutes": 0,
          "seconds": 0
        },
        "listening": {
          "hours": 10,
          "minutes": 0,
          "seconds": 0
        }
      },
      "source": "ACX: about 9,300 words per finished hour; hand calculation in content.mdx: 93,000 ÷ 9,300 = 10 h"
    },
    {
      "given": {
        "know": "length",
        "h": 9,
        "m": 5,
        "speed": 1.75,
        "daily": 30
      },
      "expect": {
        "listening": {
          "hours": 5,
          "minutes": 11,
          "seconds": 26
        },
        "days": 11
      },
      "source": "hand calculation in content.mdx: 545 min ÷ 1.75 = 311.43 min = 5 h 11 min 26 s; 311.43 ÷ 30 = 10.4, so 11 days"
    },
    {
      "given": {
        "know": "length",
        "h": 2,
        "m": 0,
        "speed": 0.8
      },
      "expect": {
        "listening": {
          "hours": 2,
          "minutes": 30,
          "seconds": 0
        },
        "added": {
          "hours": 0,
          "minutes": 30,
          "seconds": 0
        }
      },
      "source": "hand calculation in content.mdx: 2 h ÷ 0.8 = 2.5 h, 30 minutes more"
    }
  ],
  "sources": [
    "ACX (Audible), Narrate an audiobook: narrators average about 9,300 words per finished hour. https://help.acx.com/s/article/producing-and-recording-your-audiobook"
  ],
  "related": [
    "days-from-today"
  ],
  "changelog": []
}