There is no tested number for the right length. We have no measured results to quote, so this guide gives our own working rule and the samples it comes from: the shortest cut that delivers your hook and a reason to open the book.
Our working rule
We do not have measured results on length, and we will not borrow someone else's figure. Our rule is simple: stop when a stranger knows what the book is about and what to do next.
Our studio samples run from 19 to 37 seconds. We offer that as a reference for what we make, and we agree your length in the proposal.
Start from the channel
Feeds that play videos muted and in passing reward a short cut. A trailer on your own website or a book page can run a little longer, because the viewer has already chosen to look.
So we plan a full trailer and shorter cuts together, and each cut has its own length.
- Your website and book page: the full trailer.
- Reels, TikTok and Shorts: a shorter vertical cut.
- Ads: a short cut built around one line and one action.
- Email and newsletters: the same cut as your page, with a still image as the thumbnail.
Length by genre
Genre sets how much a viewer needs before they care. A thriller can open on the question and be done in half a minute. A fantasy trailer usually needs a few more seconds to show the world. A non-fiction trailer needs time for a promise and a reason to believe it.
Do
- Children's picture books: keep it short and leave room to read the lines aloud.
- Thrillers and romance: the hook in the first three seconds, then stakes.
- Fantasy and science fiction: one image of the world, then the conflict.
- Non-fiction: a question the reader recognises, the idea, then one action; it can take a little more room.
Avoid
- Filling the time because the platform allows it.
- Telling the plot in order.
- Holding a shot because it is beautiful.
- Using the same file everywhere.
What to cut when it runs long
Cut the plot first. Keep the hook, one image of the world and the line that ends the trailer.
If a shot does not help a reader want the book, it is not needed.
Length by purpose
A teaser whose only job is to stop a thumb should be the shortest piece you make. A full trailer for your book page can carry one more beat: the stakes.
Shorter cuts also make the point faster in an ad, so we usually plan the ad cut first and build the full trailer around it.
Common mistakes
Telling the plot in order, repeating the title three times, and holding a shot because it is beautiful. Each one adds seconds and removes force.
Next step
If you are making one yourself, use the steps in the main guide. If you want a studio to do it, tell us about your book and we will agree the length with you.