How to use the audiobook listening time calculator
- Enter the book length in hours and minutes. It is on the store page or the audiobook file.
- Enter your playback speed, such as 1 for normal, 1.25 or 1.5.
- Open More options to enter how many minutes you listen each day and a start date.
- Read the listening time, the time you save, and the days and finish date.
Formula
Listening time = book length / playback speed
Time saved = book length - listening time
Days to finish = listening time / minutes per day, rounded up
Finish date = start date + (days - 1)
The first day you listen counts as day 1. A speed below 1 makes the book longer, and the page then reports the extra time instead of a saving.
An 11 hour 30 minute book at 1.25x
The book is 690 minutes. At 1.25x it takes 690 / 1.25 = 552 minutes, which is 9 hours 12 minutes, and saves 2 hours 18 minutes. At 45 minutes a day that is 552 / 45 = 12.27, so 13 days. Starting on October 10, 2026 you finish on Thursday, October 22.
A 7 hour 5 minute book at 1.5x takes 425 / 1.5 = 283.33 minutes, or 4 hours 43 minutes. At half speed the 11 hour 30 minute book would take 23 hours, which is 11 hours 30 minutes longer.
Choosing a speed
Many listeners start at normal speed and raise it by small steps. Speed saves time most for books you are already following easily, and can make complex material or unfamiliar accents harder to take in. The time saved over a whole book can be large, so a small speed-up is worth trying. Narrators also differ in pace, so one book at 1.25x may sound different from another.
Making the finish date realistic
The date assumes you listen the same amount every single day. Real schedules have gaps, so add a few days or use a smaller daily amount. Use the time you can actually spare on your commute, a walk or chores rather than an ideal number.
To add up several listening sessions use the Time Duration Calculator, to count words in a text use the Word Counter and to time a session use the Online Timer.
Assumptions and limits
- The book length is the length at normal speed.
- You listen the same number of minutes every day starting on the start date.
- Playback speed ranges from 0.25x to 5x.
- Nothing is uploaded. Calculations run in your browser.
Frequently asked questions
How much time does 1.5x speed save?
A third of the time. At 1.5x a book takes two thirds as long, so a 12 hour book takes 8 hours and you save 4 hours.
How long is an average audiobook?
Lengths vary widely, from under two hours to over thirty. The page works with any length, so enter the one shown for your book.
Does the date count the day I start?
Yes. The start date is day 1. If you need 13 days and start on the 10th, you finish on the 22nd.
Can I use it for podcasts or lectures?
Yes. Any audio with a known length works the same way. Enter its length and the speed you play it at.