Book Spine And Cover Best Practices

Book Spine and Cover Best Practices

It cannot be overstated how important your book cover is. It’s the first impression, the spark that drives a reader to learn more about your book. And there’s one sure-fire way to lose that reader’s interest; a cover that is poorly designed or has a misaligned book spine.

I’ve written at length about cover design. So instead I’m going to look at a less often covered aspect of cover creation; the technical build of your file. This includes designing for bleed and correctly placing your spine, as well as the critical task of planning for variance.

What Is A Book Spine?

A book’s spine is the center of the cover, the narrow (or wide) edge where the pages are bound. There are a lot of different ways to bind a book. For our purposes, we’re going to focus on Paperback books (also called perfect bound books) because it’s one of the most commonly used binding methods. 

Perfect binding involves milling the spine edge of the pages to create a series of notches. Then the printers roll glue over the spine edge and press the book block into the cover until the glue sets. This glued edge becomes the book’s spine.

Book Cover Design Best Practices

Your book’s spine can be tricky to design correctly. While the front and back cover is a standard size based on your book’s trim size, the spine will vary in size based on the number of pages in your book. Even though your book cover has three distinct parts (the front cover, the spine, and the back cover) you need to design the cover as a single, complete file. Here’s a look at a standard, US Trade cover template:

Lulu US Trade Cover Template

We’re going to break this template down a bit and understand how to build your eye-catching custom book cover. Let’s start with the basic trimming margins.

Bleed Edge

Books, you may have noticed, are incredibly uniform. Printers achieve this by printing the pages oversized, then trimming every page to the exact same size. The stack of pages, called a book block, is cut down precisely to get that clean finish.

But doing so means losing a small portion of the page. We call this edge the Bleed Margin. You’ll notice on the template above it’s listed as the TRIM / BLEED AREA. We print the pages for your book too large by ¼ inch. So a 6 x 9 book is printed at 6.25 x 9.25 and that extra ¼ inch is trimmed away—resulting in about ⅛ inch on each side (this includes the spine side) being cut away.

For most book interiors, this is minor because the pages are white or cream and the contents (your story) are nowhere near the edge of the page.

Covers are different. Your cover is going to have art/ink right up to the edge. This means you’ll need to be careful to plan out your cover with no important content in the TRIM / BLEED AREA as shown in our book cover template.

Bleed & Your Spine 

Okay so let’s look at this template one more time.

Lulu US Trade Cover with Book Spine

That purple bar represents where a spine will go in your cover design, but it’s not THE spine for your book. Unless your interior file is exactly 22 pages long. In which case, yes, this book spine is perfect.

But for most covers, the spine width will vary based on your page count. So you have to create a spine based on the length of your book—and here lies the most challenging part of cover design.

The spine itself isn’t really affected by bleed, but its position on the cover is. Even changing nothing about your book design, the precise location of your spine can shift slightly from one printing to the next. This isn’t a print-on-demand issue either, it happens with off-set printing too.

Let’s use this cover I created as an example:

Book Cover Example

Ignoring the awful colors, you can see how I’ve created the spine as a ‘bar’ down the center of the cover. Here’s another look where I’ve highlighted the exact spine location in red.

Book Cover Spine Red

When I have this book printed, I naturally would want the RED spine area only on the spine, while the front and back cover feature their own artwork. But in practice, that won’t be exactly what happens. We call this variance.

Variance And Your Book Cover

Putting everything we just looked at together, you have a cover that is printed just slightly too big and trimmed down, and a spine set to the center of your cover file. When the edges get trimmed, the exact position of your spine might shift by a tiny fraction of an inch. Like, just the tiniest bit. This is variance. And even a tiny shift can be enough to change the appearance of your cover.

And it only matters if you create a cover with a spine like my example above. If you make your spine a stand-out color—like cherry red—it’s going to be very noticeable if the spine shifts onto the front or back cover.

Your Book, Your Way

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Spine ‘Rules’

These aren’t hard and fast rules, but if you don’t follow them and your spine runs over onto the front or back cover… well I kind of told you so.

If your spine has a unique color palette or designs, include them for at least ½ inch on the front and back sides.

That means creating your uniquely colored spine as a ‘band’ that is included (partially) over the front and back cover. Since the spine width varies, it’s hard to make a book spine template; instead, you’ll need to adjust your spine to fit your book. 

Book cover, oversized red book spine

Looks ugly, I know, but you can, of course, style your own cover to look great.

Spine text must be centered and must be small enough to allow at least ⅛ inch on either side.

Our Book Creation Guide includes a great book spine calculator. If you intend to include text on your spine, such as the book’s title and author, size the text to a point measurement that is half or less the width of your spine. I’ll get into how to figure that out next. First, I have one more rule.

Create your book cover as one complete file, not three discrete parts.

For ‌sizing, you might make a front and back cover, then layer them over the template to get the spine size. That’s fine. Merge those elements at this point and work on the final cover as a complete file.

Make sure the colors match or blend in the spine so that you’re not left with variance ruining an otherwise amazing cover! You want a professional book cover design, right? Well, even if you’ve created or commissioned beautiful artwork for your cover, a misaligned spine can ruin all of that.

Book Spine Formula 

Here’s the basic formula for the spine width in inches, for a paperback book:

(# of Interior Pages / 444) + 0.06 in

Now take note: you do NOT have to use this formula to find your spine size. If you upload your interior file, we’ll generate a template for you that includes the exact spine size based on your file. That said, sometimes you have a professional designer working on your cover before you’re ready to upload your book. In that case, you’ll want to use the formula to get the right spine size.

Let’s use this formula to think about the spine text for a 200-page book.

(200 / 444) + 0.06 = 0.51 

So that means our spine is 0.51 inches wide. I want to add some text to my spine—like the book’s title and author’s name. Just like the concern about using a unique spine color, we have to allow for variance when setting our spine text. Imagine how ugly it would be to have spine text bleeding over onto the front or back cover?

Spine Text Placement

To begin with, always center your spine text on the center of your spine—which should also be the center line of your cover file. Working from our 200-page interior file example, we’ve got a 0.51-inch spine. 

Text is usually measured in Points (pt).

Text size in Points, in MS Word

One Point is equal to 1/72 of an inch. I know, we’re doing a lot of math. I’m sorry.

Let’s say I want my text to be 14 point. Pretty standard size for cover text. If we do the math, we get:

14 x (1/72) = 0.194

That means our text is just under 0.20 inches in height. Leaving us the difference between spine width (0.51 in):

0.51 - 0.194 = 0.316

We want to include enough margin to allow for the entire bleed margin, which we know is ⅛, or 0.125 inches, on either side of the text. Last bit of math, I promise.

0.125 x 2 = 0.25 

Since 0.25 < 0.316, we know we’ll have a little more than the bleed size in extra space on the spine. We could probably go up to 16 Point font if we wanted! Giving this allowance means any minor variance in trimming at the printer won’t cause your spine text to run over onto either the front or back cover.

Carefully Design, Carefully Review

I know I threw a lot of math at you today. And for that, I am sorry. But cover design is an exacting process, in particular, because the actual printing and trimming is, by its nature, inexact. The margin for variance is tiny, just a fraction of an inch, but as we all know, your cover needs to be perfect.

Lucky for you, we provide a terrific preview tool to review your cover after you upload it. Here’s what my cover looks like, uploaded with the spine for a 200-page book, spine text at 16 Point:

Lulu Previewer with Book Spine and Cover

It’s a little tough to see, but the ‘Folds’ are showing right on the edge of the spine as blue, dashed lines. Based on the previewer, I can see that my spine placement is perfect!

Of course, there may be some variance, but with‌ the location of my spine text providing ample room on either side, I can rest assured my spine will print well. 

Book Spine Best Practices

It’s tedious, but paying careful attention to cover design is worth the headache. With the potential for very slight variance in printing affecting your spine, you really have to design with this in mind.

Think about variance and bleed when creating, consider what the book spine will look like printed, and please (please!) design a book spine that incorporates the front and back cover. Trying to build a book spine distinct from the rest of the cover is a recipe for disappointment.

Paul H, Content Marketing Manager

Paul is the Content Marketing Manager at Lulu. When he's not entrenched in the publishing and print-on-demand world, he likes to hike the scenic North Carolina landscape, read, sample the fanciest micro-brewed beer, and collect fountain pens. Paul is a dog person but considers himself cat tolerant.

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i am trying to use your cover creator powered by Canva. downloaded the template for downloaded but there’s something wrong with the .png file – can’t open it.

I have a question – say the cover and back of the book have a full BORDER surround. A thin border, but a thick cream line around all four walls. What do you do with the spine? Add same border? Leave top and bottom only?

I’m having the same problem. I’ve used the cover template for my book but whilst it fills in all the front cover details, it seems to exclude the spine? Not sure how to circumnavigate that. Any ideas?

Like Janet, I’m using the LULU preset design and I can’t see where you input information for the spine. Any ideas please?

I used Lulu’s template to assist in creating a book cover, however, it remained a mystery on how to include the title and authors’ names on the spine.Will LuLu add the title and author’s, and co-author’s, names on the printed book’s spine?

I’ve downloaded the cover template from Lulu and I can’t seem to get the guide lines for the cover to show up in Word. It would be helpful for lining up the photos and text boxes. You give measurements, but how do I know what the measurements are on my project? Also when I designed the cover using the template I decided to just see how it will look, converted to pdf for upload and there were blocks of white where they were not in the docx version. What am I doing wrong?

I have had great results with the new Lulu cover system, once you ironed out the wrinkles.
Covers come out exactly as I want them.
I make my cover layout with my own design software and then configure them to fit the in-depth preview in the new cover tool. Congrats on working out the problems under the current difficult working conditions!
E.M. Camarena

Two problems for me:
Firstly, can you amend that description so it includes metric measurements, please? An automatic calculator with the maths done would be a big help, as it is the calculation part that has stalled me.
Secondly, can you amend the new cover creator to allow the user to add their own purchased ISBN barcode, please?
Thank you.

Dear Paul,

I understand that lulu had to update with the recent abolition of Flash.

Is it the case that Lulu is currently trying to fix the situation so that the new platform will be as accessible as the previous flash version?

The reason I ask is that I have been having trouble accessing the new updated version – or the version left behind after flash.

I find it impossible to navigate and use.

Hopefully the new version should be more easily accessible.


P.S. I have been having trouble trying to access my old account – the one I had before the new updates. In my old account I have over 300 projects.

Every time I try to login and it asks me to verify the email, I look into my emails and see that it hasn’t sent one. No matter how many times I press the ‘Re-send email’ it never appears. I’ve had to create a spare account just to try and get in contact with customer support.

When will I be able to access my older account?

I am trying to create a new larger edition of the book I have successfully four prior times. But using the Lulu cover creation tools I am unable to customize the spine or to place the image on the back cover that I used before.

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