We have no figure to promise you, and we will not invent one. The sources we read are author blogs, trailer vendors and marketing guides, and none of them publishes measured sales data. What we can do is show where a trailer helps, where it does not, and how to find out for your book.
What the evidence says
The honest summary is that the evidence is thin. Opinions among authors are mixed: some think trailers pay back when they are made well, others doubt them, and a common warning is against trailers that run long or give away the plot.
Because most of what is written comes from people who make or sell trailers, we treat it as opinion, not proof.
Where it helps
A trailer gives a reader who already found your book a fast, vivid reason to buy. It helps a book page, a newsletter or a launch post stand out.
Do
- A book page that already gets visitors.
- A newsletter to readers who know you.
- A launch post with a clear link.
- Ads that point to one buy or sign-up link.
Where it does not
A trailer does not make strangers find the book on its own. Without a place for it to be seen, it will not sell.
Avoid
- Posting it once and waiting.
- Sending viewers to a page with no buy link.
- Using one horizontal file on every platform.
- Judging it by views alone.
A better question
Instead of asking whether trailers sell books, ask what you want a viewer to do after watching. If the answer is a click, a sign-up or a preorder, you can measure it.
How to find out for your book
Compare the same book page with and without the trailer, or two cuts sent to similar audiences, and look at clicks to your buy link. Small tests tell you more than general claims.
- One link per cut, with its own tag so you can tell cuts apart.
- The same audience for both cuts.
- A fixed window, such as one week for each.
- Write down the click count before you change anything.
Our view
A trailer is one part of a launch. It is strongest when the book page, the newsletter and the posts all agree on one message.
If you want one, we start from the job you give it, then plan the cuts that do that job.