How long will this audiobook take?
Enter the audiobook's length, or the book's word count, and the speed you listen at. See how long it takes, the time you save, and how many days it lasts at your daily listening time.
- Listening time
- 7 hours, 40 minutes
At 1.5× the audiobook takes 7 hours, 40 minutes.
- Time saved
- 3 hours, 50 minutes
- Length at 1×
- 11 hours, 30 minutes
- Days to finish
- 11
Listening time: 7 hours, 40 minutes. At 1.5× the audiobook takes 7 hours, 40 minutes.
How to calculate
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.
Example with the default inputs (I know Its length, Hours 11, Minutes 30, Playback speed 1.5, Minutes a day 45): At 1.5× the audiobook takes 7 hours, 40 minutes.
Method: listening time = length ÷ speed; length from words = words ÷ 9,300 an hour; days = ⌈listening minutes ÷ minutes a day⌉
- 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.
Worked examples
Each example is checked against the calculator on every build.
- I know Its length, Hours 11, Minutes 30, Playback speed 1.5, Minutes a day 45 gives Listening time 7 hours, 40 minutes, Time saved 3 hours, 50 minutes, Days to finish 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
- I know Word count, Words 93,000, Playback speed 1 gives Length at 1× 10 hours, Listening time 10 hours.Source: ACX: about 9,300 words per finished hour; hand calculation in content.mdx: 93,000 ÷ 9,300 = 10 h
- I know Its length, Hours 9, Minutes 5, Playback speed 1.75, Minutes a day 30 gives Listening time 5 hours, 11 minutes, 26 seconds, Days to finish 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
- I know Its length, Hours 2, Minutes 0, Playback speed 0.8 gives Listening time 2 hours, 30 minutes, Time added 30 minutes.Source: hand calculation in content.mdx: 2 h ÷ 0.8 = 2.5 h, 30 minutes more
How it works
- Length at 1×: the hours and minutes you enter, or the word count ÷ 9,300 words an hour.
- Listening time = length at 1× ÷ playback speed.
- Time saved = length at 1× − listening time, when the speed is above 1×. Below 1× the difference is time added.
- Days to finish = listening time in minutes ÷ minutes a day, rounded up to a whole day. It is only shown when you enter minutes a day.
Every time is shown in hours, minutes and seconds, rounded to the nearest second (a half second rounds up). Time saved or added is the difference between the two rounded times, in whole seconds. Time saved is shown only when the rounded listening time is shorter than the rounded length, and time added only when it is longer; when both round to the same second (1 minute at 1.00001×), neither is shown. Days use the same float-noise rule as other counts: a value within 0.000000001 of a whole number counts as that whole number. The length must be more than zero.
Worked examples by hand
11 h 30 min at 1.5×, 45 minutes a day. 11.5 ÷ 1.5 = 7.667 h = 7 h 40 min. Saved: 11 h 30 min − 7 h 40 min = 3 h 50 min. 460 min ÷ 45 = 10.2, so 11 days.
A 93,000-word book at 1×. 93,000 ÷ 9,300 = 10 hours.
9 h 5 min at 1.75×, 30 minutes a day. 545 min ÷ 1.75 = 311.43 min = 5 h 11 min 25.7 s, which rounds to 5 h 11 min 26 s. 311.43 ÷ 30 = 10.4, so 11 days.
2 h at 0.8×. 2 ÷ 0.8 = 2 h 30 min, which is 30 minutes added.
Other questions people ask
How long is an audiobook at 1.5× speed?
Divide the length by 1.5. An 11 h 30 min audiobook takes 11.5 ÷ 1.5 = 7.67 hours, or 7 h 40 min, which saves 3 h 50 min.
How many words are in an hour of audiobook?
ACX, Audible’s audiobook production marketplace, says narrators average about 9,300 words per finished hour. A 93,000-word novel is about 10 hours at 1×.
How do I estimate an audiobook’s length from a book?
Choose Word count and enter the words. The length at 1× is words ÷ 9,300 hours. Page counts are less reliable, because words per page vary with the font and layout.
How many days will it take me to finish?
Enter how many minutes a day you listen. The calculator divides the listening time in minutes by that and rounds up. 460 minutes at 45 minutes a day is 10.2, so 11 days.
Does slower playback add time?
Yes. At 0.8× a 2 hour audiobook takes 2 ÷ 0.8 = 2.5 hours, 30 minutes more. The calculator shows this as time added.
Is the length on the store page at 1×?
Yes. Stores list the length of the recording at normal speed. The listening time here is that length divided by your speed.