Calculate Image Size for Print and eBooks

With the Theme Builder in Atticus, you can create a custom theme for your books that includes a variety of header styles using images. To ensure you fit the images properly to fit your aesthetic, this article will share with you some sizing and resolutions suggestions for both Print and eBooks. 

Creating Your Custom Theme

You can choose one of the pre-formatted themes for your book, but if you’d like to achieve a unique aesthetic, you may want to set up and save a custom theme.

To start, click on the Create Custom Theme button in the formatting tab of Atticus, with your book open. 

You have three choices:

  • No Image
  • Background Image
  • Image Element

No Image will simply style your chapter number, chapter title, and subtitle. You can change the font, sizing, and alignment for each element. You can also choose settings for your print versions header and footer elements. 

Background Image will place your image behind the text of your header and, for print versions, the body content of your book. eBooks do not offer full bleed nor will they work well with images behind the body content, so you are restricted to just the header setting for digital versions. 

The Image Element will place your Image above or below the elements in your header, depending on your settings. 

Let’s take a closer look at the various image options. 

Background Image

If you want to use the Background Image option and you are planning on exporting your manuscript to both print book and digital book formats, it’s best to choose an image that will work well as a background behind your body content for your print version as well as look great if it is only featured in the header, for your eBook version.

Trim, Margins, and Bleed

For print versions the correct size will depend on the trim size of your book. Atticus will extend the image to the very edges of your page if you size the image to incorporate bleed. It helps to understand some basic print formatting terminology:

  • Trim Size: this is the final width and height of your book. The most common trim size for most self-published books is 6” x 9”
  • Margins: are the space inside the trim that creates a safe border within each page so that the text and content of your book is not cut off by the printer or lost to the inner crease of the book
  • Bleed: refers to amount of space beyond the trim size that is necessary to include in order to ensure all images, particularly background or “full bleed” images, are safe within the boundaries of the final page after it has been cut at the printer 

If you print with KDP, Amazon requires all full bleed PDFs to extend 0.125” beyond the chosen trim size of a book on the top, bottom and outer edge.

When you insert an image into the background of either the header or full page, you will want to have the correct full bleed settings.

Header Background Image [Print and eBook Versions]

Whether you’re planning on having your book printed or used exclusively digitally, having an image in the background solely can look stunning, especially if you get the sizing correct. 

For the Header image, you will need to calculate the bleed for the width of your book only, and then choose a height that suits the aesthetic of your image.

In print versions, the image will extend down the page according to the size you create, and the body content will print over the image if necessary. For eBooks, the body content will start after the image, regardless of the size.

Remember when you’re choosing your image that it costs more to print images in color, so it’s a good idea to choose images that will be as attractive in greyscale as in full color.

To calculate the bleed required for your chosen trim size, use this formula:

  • Single Page Width in Inches: Trim Size Width + 0.125″
  • Width of 2 page spread: (Trim Size Width + 0.125″) x 2
  • Height in Inches: Trim Size Height + 0.25″
  • Pixels = inches x ppi

What is PPI?

PPI is pixels per inch. You may also see this referred to as DPI, or dots per inch. For a high resolution image, use 300 ppi

Here is a handy reference chart:

Full Background Images [Print Versions]

As previously mentioned, for print versions, the background image will extend down the page according to the total size of the image, and the body content will print over the image. For eBooks, the body content will start after the set header space, regardless of the size of the image.

There is no exact sizing available for eBook versions because the space will adjust depending on the content in your header.

It’s a good idea to choose an image that will not only look good in greyscale as well as full color, but also that will look appropriate as a full page image as well as simply a header image.

To use a full bleed background image, you will need to use the bleed settings for the trim size of your book. You can use the same formulas as listed above.

Image Element

The Image Element theme inserts an uploaded image in one of four locations in your header:

  1. Above the Chapter Number
  2. Between the Chapter Number and the Chapter Title
  3. Below the Chapter Title
  4. Below the Subtitle

You can align the image as you prefer and adjust the width of the image up to 100%, which is full bleed in print books and to the maximum margins allowable on an eBook.

You may want to use the bleed settings of your book’s trim size as the maximum width of your image and adjust from there within Atticus if you choose. The image will maintain the proper proportions as it scales.\

Individual Chapter Images

If you want to have a single image used throughout your book, repeating on each chapter, you will reduce the file size of your book, at least for eBook versions. 

To really set your book apart, however, you can also create header images that are unique to each chapter of your book. This short, silent video will walk you through that process:

Last Updated: 10/20/2022

Was this tutorial helpful?