Designing Cover and Understanding Images

The most frequent reason why book submissions do not go through in one go at is because cover is not submitted in a print ready format. The bad news is that it needs some technical understanding to get your cover right. The good news is that it is not too difficult to understand. You only need to spend a few minutes of your time. Let’s do it right now.

Parts of the Cover

First, let’s understand the different parts of the cover.

  1. Front Cover: Should be self explanatory.
  2. Back Cover: Should be self explanatory.
  3. Spine: This is the part that covers the thickness of the book.
  4. Bleed: Bleed is not a part of the final cover, but needs to be present in the print ready cover file. This is extension of the background of the cover a bit beyond the actual size. The book is printed and bound, usually on the paper of size bigger than the final intended size. After the binding is done, the book is trimmed to the final size. This ensures that all the pages are trimmed evenly and the book looks good. Now, even the best trimming processes will not be completely accurate. There will always be a margin of error in the size to which the book is trimmed. If the cover is printed in exactly the final size, then a slight error in trimming could result in a white line on the sides. To avoid this the background is extended a bit. The part you see in the image below outside of dotted lines on all four sides is the bleed.


Next thing to understand is the position of the different parts of the cover on the print ready file.

  • Cover is printed on a single page. So, a print ready cover will have front and back covers as well as spine on a single page in a single file. You may initially design front and back covers separately, but finally they have to be put together on a single page.
  • To understand the correct position of the various parts on that single page, open any book you have and then look at the cover. For most of the Indian languages and English, which are written left to right, the binding is done on the left side of the book. So, if you are looking at the cover of an open book, back cover will be on the left side, spine in the middle and front cover on the right side. This is exactly how the print ready cover should have these parts positioned. For Urdu and other Right to Left languages, the position of front and back cover would be switched. In either case, bleed goes around the entire cover. Never design separate front cover, back cover and spine with bleed on all sides. Bleed goes only around the entire cover, not around the individual parts! I know I am being repetitive here, but that’s intentional.

Size of the Cover

Now, let’s come to the size of the cover. Dimensions will be a bit different for a hard cover book. To keep things simple, let’s talk about perfect bound (normal soft cover books) and saddle stitched (center stapled) books.

  • Front Cover and Back Cover should be a no brainer. You want the front and back cover in the same size as the trim size you have decided for the book. So, for a book of 5″x8″ size, the front and back cover should be of 5″x8″ size
  • Spine is the tricky part because its width will obviously vary with the number of pages. It is important to work with your printer to ensure that your spine thickness is right. Else, everything on front and back cover will be placed wrongly and all your design will go down the drain. Offset printers may sometimes ask you for front, back and spine in separate files in an editable format (photoshop, illustrator, indesign or coreldraw typically) so that they can adjust the spine width if needed. This model is not feasible for most Print on Demand (POD) vendors. They would, generally, provide clear formula on spine width as a function of number of pages. Use the formula and stick to it strictly. Because of the spine width part, the cover design can be finalized only after the interior is formatted and we know the final number of pages. Unless you are comfortable with graphic design or have a designer at your disposal to keep making adjustments, you may not want to start cover design before interior formatting in final.
  • Saddle stitched books will not need a spine, although the number of pages for which you can do saddle stitching is usually limited.
  • Bleed should be added to the entire cover. Typically POD printers will specify the bleed you should put in your design. If your printer has asked for the front, back and spine as separate files (mostly in case of offset printer), add the bleed only on the relevant side of each part. Assuming Left to Right language for the book
    • Front Cover: Top, right and bottom should have the bleed, left should NOT
    • Back Cover: Top, left and bottom should have the bleed, right should NOT
    • Spine: Top and bottom should have the bleed, left and right should NOT
  • Typically the cover design specifications would tell you the total size of the cover and also the sizes of individual parts in it (WIDTH: bleed+trim width (back cover) + spine width + trim width (front cover) + bleed; HEIGHT: bleed + trim height + bleed) . It is extremely IMPORTANT to stick to both parts of the specification. Common mistakes people make are
    • Having correct overall size for the cover, but random sizes for individual parts (front cover, spine and/or back cover)
    • Having correct size for front and back cover, but putting in spine of a random width
  • Be careful of such mistakes, as you may hate the book that comes in your hand even if the design and production quality was the best otherwise.

Reoslution of the Cover

Finally a very important part about a concept called resolution. In the world of computers, the measure of length is in pixels. Pixels have no equivalent in physical world. So, you can not say something like 1 inch = N pixels. It is always decided by the device displaying the image as to how many pixels are displayed in inch. This measure is called pixels per inch or PPI. DPI is a term more commonly used for PPI, even though its not the correct usage. Without getting into details, let’s say that DPI and PPI are interchangeable terms for our discussion. Since DPI is the word more commonly used, we will also use DPI here. So, when you are trying to create an image of certain width and height in inches on the computer, you also need to know at what DPI you have to create it at. Typically for on-screen display (on monitor) 72 or 96 DPI is good. But for print the image must be at 300 DPI. Anything lower than that would result in bad print even if it appears good on screen.

To make this concept clear, let’s take a simple example. Suppose you have to design a cover for a book of 5″x7″ size. The spine width, given the number of pages, is 0.35 inch and you are required to put in 0.2 inches of bleed on all sides. Then

  • Total size of the cover in inches is
    • Width: 0.2 (bleed) + 5 (back cover) + 0.35 (spine) + 5 (front cover) + 0.2 (bleed) = 10.75
    • Height: 0.2 (bleed) + 7 (cover) + 0.2 = 7.4
  • This cover has to be designed at 300 DPI
  • So, the size in pixels would be
    • Width: 10.75 x 300 = 3225
    • Height: 7.4 x 300 = 2220

In most modern image editors, you should be able to specify the width and height in inches/mm and the DPI. So, you do not need to worry about the pixels. But it is important that you specify the DPI correctly.

In Photoshop, when you create a new image, you will see a dialog like this. You can specify PPI/DPI in Resolution field.

In Gimp (a free and open source alternative to Photoshop) the default dialog will be the following and you would have to click on the “Advanced Options” to get the DPI setting

Clicking on “Advanced Options” will show the place to specify DPI (X resolution and Y resolution).

So, now you know all about the image sizes and how to get the right size of your cover.

If you need to prepare a cover for publishing on, you may check out the following options

[Self Publishing Guide] Self Publishing your Book – Step 2: Design the Book

This post is an excerpt from our Self Publishing Guide for Indian Market. If you have not, you may want to read the following post in this series before starting on this one

The book design is in two parts – the interior of the book and the cover.

Book interior. The layout, fonts, size, etc of the book needs to be designed according to the target audience. For instance, a children’s book will have more illustrations with larger, well spaced out fonts and an overall endearing look. On the other hand, a thriller will have a denser text with an easy-to-read font. Technical books are likely to have more diagrams and tables.

Book cover. Unfortunately, most people do judge a book by its cover. So, design an eye-popping cover for your prized work.

Suggestions for an attractive, effective book cover:

  • Do include the author’s photograph somewhere. This gives the author behind the book a personality and helps readers connect better.
  • Use the back cover to show positive reviews of the book and a gripping synopsis of its content.
  • The design of the front cover, title and subtitle should arouse the reader’s curiosity.
  • The book title and the author’s name should be printed on the spine for better visibility on a bookshelf. (This may not be possible for thinner books.)