Getting narrator quotes
Narrators price per finished hour, so the hours figure is the number every quote starts from. The audiobook cost calculator does the sums.
Free tool
Audiobook Length Calculator: How Many Hours Is Your Book?
Enter your word count, or your page count and words per page, choose a narration pace, and this audiobook length calculator shows how long the finished audiobook will run, roughly how many 20 minute chapters that makes, and the AI credits it would take to narrate.
Audiobook length
8 h 36 min
Standard novel
Words
80,000
Chapters (about 20 min)
26
AI credits (standard)
4,104
AI credits (premium)
5,928
Three steps to your audiobook length
- 1
Enter words or pages
Choose “I know the word count” and type it or drag the slider, or switch to pages and set the words per page (275 by default).
- 2
Pick a narration pace
Slow (130), conversational (150), audiobook (155) or fast (170) words per minute. Most finished audiobooks sit near 155.
- 3
Read the results
See the finished length with a size band, the total words, a chapter estimate at about 20 minutes each, and AI credits for standard and premium voices.
Word count to audiobook length at three paces
Quick answers for common manuscript sizes, rounded to the nearest minute.
| Words | 155 wpm (audiobook) | 130 wpm (slow) | 170 wpm (fast) |
|---|---|---|---|
| 20,000 | 2 h 9 min | 2 h 34 min | 1 h 58 min |
| 50,000 | 5 h 23 min | 6 h 25 min | 4 h 54 min |
| 70,000 | 7 h 32 min | 8 h 58 min | 6 h 52 min |
| 90,000 | 9 h 41 min | 11 h 32 min | 8 h 49 min |
| 120,000 | 12 h 54 min | 15 h 23 min | 11 h 46 min |
| 150,000 | 16 h 8 min | 19 h 14 min | 14 h 42 min |
| 200,000 | 21 h 30 min | 25 h 38 min | 19 h 36 min |
Timing a short script instead of a book? The words to minutes calculator works in minutes and seconds.
Page count to audiobook hours
Page counts vary with trim size and font, so the calculator lets you set words per page. These rows use 275 words a page, typical for a trade paperback novel.
| Pages | About this many words | Audiobook length at 155 wpm |
|---|---|---|
| 100 | 27,500 | 2 h 57 min |
| 200 | 55,000 | 5 h 55 min |
| 300 | 82,500 | 8 h 52 min |
| 400 | 110,000 | 11 h 50 min |
| 500 | 137,500 | 14 h 47 min |
Dense nonfiction holds more words per page; large print and children’s books hold far fewer. A word count is always more accurate than pages.
What authors use an audiobook hours calculator for
Budgeting AI narration
Credits for standard and premium voices appear next to the length, so you know the cost before you upload a word.
Planning chapters
The chapter estimate assumes about 20 minutes each. If your draft has far fewer chapters, some of them will run long.
Writing to a target
Aiming for a six hour novella or a ten hour novel? Work backwards from hours to the word count you need.
Listing the running time
Stores and sales pages show the length up front. Have a realistic figure ready for pre-order pages and newsletters.
Planning file sizes
An M4B at 64 kbps takes about 29 MB per hour, so a 15 hour book is around 430 MB. Useful when you share files directly.
How to work out audiobook length by hand
The core formula is hours = words ÷ (words per minute × 60). At an audiobook pace of 155 words per minute, one finished hour holds 155 × 60 = 9,300 words, so an 80,000 word novel runs 80,000 ÷ 9,300 = 8.6 hours, or about 8 hours and 36 minutes.
From pages, multiply first: words = pages × words per page. A 300 page novel at 275 words a page is 82,500 words, which comes to roughly 8 hours and 52 minutes. Count a sample of three full pages and average them if you are unsure of your own figure.
Pace is the variable to watch. Thrillers and comedy are often read a touch faster, while literary fiction, poetry and picture books are read more slowly to let lines land. Heavy dialogue adds small pauses between speakers. If you know your genre runs slow, pick 150 or 130 rather than the 155 preset.
For AI narration, convert words to characters at about 5.7 characters per word, then apply the voice rate: credits = words × 5.7 ÷ 1,000 × credits per 1,000 characters. With Standard voices at 9 credits, 80,000 words comes to about 4,100 credits; with Premium voices at 13, about 5,900. That is the same arithmetic the audiobook length calculator runs above.
Finished length is not listening time
The audiobook length shown in stores is measured at normal speed. Many listeners use 1.25x to 2x, so an 8 hour 36 minute book takes 6 hours 53 minutes at 1.25x, 5 hours 44 minutes at 1.5x and 4 hours 18 minutes at 2x. Narrators and studios always price on the 1x figure.
Checking the estimate against your real chapters
Once the audiobook length estimator gives you the hours, check how they split. The free EPUB chapter extractor shows the word count and narration time of every chapter in your actual file, and the audiobook chapter length guide explains what listeners expect from each one.
Then hear it rather than estimate it. Upload the manuscript to the AI audiobook generator, where every speaking character gets a separate AI voice, and generate a short sample with the 100 gift credits (valid for 7 days, about 12 minutes on Standard; usage varies by text and voice tier) you get when you sign up with Google. The finished file shows exactly how close the estimate was.
Audiobook length calculator FAQ
How many hours is a 100,000 word novel as audio?
About 10 hours and 45 minutes at a typical 155 words per minute. A slower narrator at 130 stretches it to almost 13 hours, and a fast one at 170 brings it under 10.
How many words does one finished hour hold?
About 9,300 words at 155 words per minute, the pace this calculator uses as its audiobook preset. That falls to 7,800 words at a slow 130 and rises to 10,200 at a fast 170.
How long is an audiobook for a typical novel?
Many novels land between 8 and 12 hours, which matches 75,000 to 110,000 words. Novellas often run 2 to 5 hours, and epic fantasy can pass 20. Your own word count in the audiobook length calculator gives a much better answer than an average.
What page count makes a 10 hour audiobook?
Roughly 340 pages at 275 words a page. Ten hours at 155 words per minute is about 93,000 words, so a book with denser pages reaches ten hours in fewer pages.
Does AI narration run at the same length?
Close to it. AI voices read at a natural audiobook pace, so the estimate holds well. Directions such as [slowly] or long pauses in dialogue can add a little, and fast-paced voices can take a little off.
Why does my real chapter count differ from the estimate?
The estimate simply divides the running time into 20 minute chapters. Your book keeps its own chapters, which may be shorter or longer, and the audiobook follows them. Load the file into the EPUB chapter extractor to see the real split.
Is the audiobook length calculator free?
Yes, with no account and no limit on how often you use it. All the arithmetic happens on your device, so nothing you type is stored or sent anywhere.
Turn your audiobook length into real audio
Take the hours from the audiobook length calculator and narrate a short sample free with a full AI cast.