Book Cover Images: How to Choose Stock Photos That Sell

Readers learn genre conventions by exposure and read them faster than they read words. Romance runs warm and photographic. Thriller runs cold and isolated. Horror withholds rather than shows. An image that ignores those conventions confuses the exact reader you were trying to attract.

Open your subgenre on Amazon, study the top twenty, and note what the imagery has in common before you open a single stock site.

A cover needs one focal point that carries the idea, with everything else arranged around it. Two competing elements produce a cover that reads as neither, and the problem gets worse the smaller the image gets.

Pick the image that communicates your book’s central tension in one object, then let composition and type build around it.

This is the most common practical failure, and it is pure arithmetic. A print cover needs 300 DPI at full trim size plus bleed. For a 6 by 9 inch paperback that means roughly 1,875 by 2,775 pixels for the front alone, and more again for a full wrap.

A 1,000-pixel-wide image cannot become a paperback cover, however good it looks on screen. Check the pixel dimensions on the stock site before you build a design around it.

There is a difference between meeting a genre convention and using the same photograph as everyone else. Conventions are palette, composition and mood. Cliches are the specific stock images that have been used four hundred times already.

If several of the top ten covers in your subgenre use the same lone-figure-on-a-cliff shot, using it too makes you forgettable rather than current. Search the image on the stock site and see how many books already carry it.

Colour registers before the reader processes a single word, so it is the fastest genre signal you have. Warm pinks and oranges read as romance, warmth and energy. Cool blues and greens read as calm, mystery and science fiction. Desaturated palettes read as dystopian or literary.

An image with the wrong dominant colour can often be graded, but it is far easier to choose one that already sits in your genre’s range. Our colour theory guide breaks this down by genre.

A book you sell is commercial use, and stock licences are not all the same. This is the rule most often broken by accident.

Standard licence usually covers unlimited digital use including ebooks, but caps print runs. Shutterstock’s standard licence, for example, covers up to 500,000 print copies. Extended licence removes that cap and is what you want for a book you expect to sell widely.

Free for personal use excludes exactly what you are doing. Editorial use only is never usable commercially, no matter how perfect the image. And an image of a recognisable person needs a model release before it goes on a cover you sell.

Before you buy, drop the image into a rough layout and shrink it to 150 pixels wide. If the focal point disappears or the composition turns to mud, the image is wrong regardless of how good it looks at full size. That is the screen where readers actually decide.

Then show it to someone who has not read the book and ask what genre they think it is. Authors are too close to their own work to judge this, and a five-second reaction from a stranger is worth more than a week of your own deliberation.