Audiobook speed calculator
Enter the length of an audiobook and a playback speed. The calculator gives the listening time, the time saved against 1x, and the day you finish at the minutes you listen per day.
- Listening time at 1.5x
- 6 h 40 min
- Time saved
- 3 h 20 min
- Finish by
- 9 days
This audiobook at every speed
| Speed | Listening time | Time saved |
|---|---|---|
| 1x | 10 h | 0 min |
| 1.25x | 8 h | 2 h |
| 1.5x | 6 h 40 min | 3 h 20 min |
| 1.75x | 5 h 43 min | 4 h 17 min |
| 2x | 5 h | 5 h |
| 2.25x | 4 h 27 min | 5 h 33 min |
| 2.5x | 4 h | 6 h |
| 2.75x | 3 h 38 min | 6 h 22 min |
| 3x | 3 h 20 min | 6 h 40 min |
| 3.25x | 3 h 5 min | 6 h 55 min |
| 3.5x | 2 h 51 min | 7 h 9 min |
How the listening time is computed
Listening time is the length of the audiobook divided by the playback speed. A 10 hour audiobook is 600 minutes. At 1.5x it takes 600 / 1.5 = 400 minutes, which is 6 hours 40 minutes. The time saved is the difference: 3 hours 20 minutes.
Each step up in speed saves less than the one before. For the same 10 hour book, going from 1x to 1.5x saves 3 hours 20 minutes. Going from 2.5x to 3x saves 40 minutes.
The finish date divides the listening time by the minutes you listen per day and rounds up to whole days, counting today as the first day. At 45 minutes a day, 400 minutes takes 9 days.
Speeds and narration rates
The slider runs from 0.5x to 3.5x because that is the range Audible offers, in steps of 0.1. The presets are every quarter step from 1x to 3.5x.
To use this as an audiobook length calculator for a book you have only as text, start from the word count. ACX estimates that narrators read about 9,300 words per finished hour, or 155 words per minute. An 80,000 word book is about 8 hours 36 minutes at 1x. The reading time calculator does that conversion.
At 2x, a 155 words per minute narration reaches you at 310 words per minute. The average adult reads non-fiction silently at 238 words per minute (Brysbaert, 2019), so 1.5x is already close to normal reading pace and 2x is past it.
Limits of the number
The calculator says when the audio ends. It says nothing about how much of the book you will be able to explain afterwards. A recording cannot be asked a question, at 1x or at 3x, and a faster recording leaves less room to notice that something did not make sense.
The evidence on listening and learning is covered in alternatives to Audible for people who listen to learn. Read-aloud apps that go faster still are compared in Speechify alternatives.
Common questions
- How long is a 10 hour audiobook at 1.5x speed?
- 6 hours 40 minutes. Ten hours is 600 minutes, and 600 divided by 1.5 is 400 minutes. You save 3 hours 20 minutes against 1x.
- How much time does 2x speed save?
- Half. A 12 hour audiobook takes 6 hours at 2x. Going from 2x to 3x saves less than going from 1x to 2x: the same book takes 4 hours at 3x, a further 2 hours.
- How do you calculate audiobook length from a word count?
- Divide the word count by 9,300 to get hours at 1x. That is the figure ACX, the audiobook production service owned by Audible, uses to estimate finished length, and it works out to about 155 words per minute. A 90,000 word book runs about 9 hours 41 minutes.
- What speeds does Audible offer?
- Audible lets you set narration speed from 0.5x to 3.5x in steps of 0.1, and it remembers a different speed for each title. The slider on this page covers the same range.
Understand reads an article or PDF aloud and stops when you ask a question. Open Understand