About The Books Insider
The Books Insider is a data project about audiobooks. We answer the questions listeners actually search — how long is this audiobook, when will I finish it, who narrates it, is it long for its genre — with numbers we compute ourselves across a dataset of 2,000 audiobooks in 5 genres, instead of copying marketing blurbs.
Every book page has a finish-time calculator (your minutes per day × playback speed → a real finish date), length percentiles against the book's genre, and narrator information when it can be reliably credited.
How we compute listening times
Where a verified audiobook running time is available from our sources, we use it as-is. Where it isn't, we estimate it from the book's page count and clearly label it as an estimate:
listening hours ≈ pages × 275 words per page ÷ 9,300 words heard per hour
275 words per page is a standard typesetting average; 9,300 words per hour corresponds to the ~155 words-per-minute pace common in commercial audiobook narration. Real narration pace varies by a few percent either way, so treat estimates as good to roughly ±10%. Every estimated figure on this site is marked “est.” or “estimated” — if it isn't marked, it's a real duration.
How the other stats work
- Genre percentiles (“longer than N% of romance audiobooks”) are computed within each genre cohort of our dataset — not against some unstated universe.
- Finish times are arithmetic on the book's hours: minutes per day and playback speed → days to finish and the calendar date.
- Narrator data appears only when a narrator is explicitly credited in our source metadata. When we can't credit one reliably, we show nothing rather than guess — a wrong narrator is worse than none.
- Ratings come from Open Library's reader ratings and are shown with their counts. We never fabricate or adjust ratings.
Data sources
- Open Library — bibliographic records, page counts, subjects, reader ratings, cover images.
- Apple's public iTunes Search API — audiobook editions, descriptions and narrator credits.
The dataset is refreshed monthly. Each page states when its numbers are computed estimates; the current dataset covers 2,000 titles with an average length of 10.8 hours.
How the site is funded
The Books Insider is reader-supported: we participate in the audiobooks.com affiliate program and may earn a commission when you start a free trial through our links — at no cost to you. The books covered here are the ones readers rate and reach for, never the ones that pay best — commissions have no input into any number on this site. The full picture is on theaffiliate disclosure page.
Contact
Questions, corrections, or a data error you've spotted:[email protected]. Corrections to computed numbers are treated as bugs and fixed in the next refresh.