📐 Sizes, spines and printers

Book cover dimensions, start to finish

A print cover is one wrap — back, spine and front on a single sheet — measured outward from your trim size. Here is where every number comes from, and what goes wrong when one of them is off.

How to calculate spine width

Spine width is page count times paper bulk, and every printer's paper bulks differently. The same 300-page novel has a different spine at each of them, which is why one formula copied off a blog won't do.

Choosing a trim size

Trim size is the finished page size of your book, and it is the first decision you make — because page count, spine width, margins, cover proportions and the cost of every copy are all derived from it.

Where to print: KDP, IngramSpark, Lulu and B&N Press

Four print-on-demand routes, what each one is actually for, and the technical fact that catches most authors out — each printer measures a book differently, so one cover file is not valid everywhere.

Paperback, hardcover, dust jacket: what changes

The three bindings are three different physical objects, not three finishes of one file. A hardcover wrap is bigger than its trim size, its spine is thicker, and a jacket adds two flaps that need copy.

Why print files get rejected, and how to not be rejected

Almost every rejected print file fails for one of ten reasons, and the same ten come up at every printer. Here they are, most common first, with what the printer sees and how to fix it.

Bleed and safe area, explained once

Two ideas hold every print file together — artwork that runs past the edge, and anything you care about held well inside it. Learn them properly once and most rejections stop happening.

Designing a spine people can read on a shelf

The spine is the only part of your cover most bookshop and library browsers ever see, and it is the part authors design last and worst. Here is what belongs on it, how large the type can be, and when to leave it blank.

What goes on the back cover

The back cover is a sales page with a fixed layout problem: a barcode block that cannot move, a safe area that cannot be crossed, and less room than you think. Here is what belongs on it, in order.

Metric trim sizes, and books printed outside the US

The standard self-publishing trims are in inches because print-on-demand grew up in the United States, while much of the world buys A5, B-format, demy and royal. What they correspond to, and how to choose one.

Printing in more than one country

Print-on-demand routes each order to a plant near the buyer, so one book can be printed in several countries without you arranging anything. What that means for color, paper and delivery, and what to do about it.

The printer's template, and how to read it

Every printer will generate a cover template for your exact book, and most authors either ignore it or design inside it. It is neither a canvas nor a decoration. It is the geometry they will cut to.

Fixing a book that is already published

Print on demand means no warehouse full of the old version, so a typo found in week two is worth fixing. What you can replace, what it costs, and the page-count trap.

Paperback, hardcover, or both

Which editions are worth making, and in what order. Hardcovers cost the reader more and sell to people who already want the book, so most first titles should lead with the paperback and add a hardcover for a reason.

Dust jackets, and the extra geometry they need

A jacket is a printed sheet wrapped around an already-bound hardcover, with two flaps and four folds that nobody plans for. What goes on the flaps, why the front panel starts at the fold, and where bleed applies.

Why a printed cover never lands exactly where you put it

A book is printed first and cut afterwards, and cutting has a tolerance. The wrap drifts, the fold misses the spine, one edge loses more than the other. Here is how to design so none of it shows.

Square, tall and pocket-sized: leaving the standard trims

A square photo book or a tall, narrow poetry collection can be exactly right. It also narrows where you can print, how you can distribute, and how your book sits beside its competition. Here is the trade.

Long books, page limits, and splitting into volumes

Print on demand has hard page ceilings, and a very long manuscript runs into them. You have four levers — typesetting, trim, paper and splitting the book — and each one costs something different.

Comics and graphic novels in print

When the page is art rather than text, the print rules bite harder. Bleed on every page, a gutter that swallows the middle of a spread, page parity that decides what faces what, and color that costs more.

Working with a local printer instead of print-on-demand

A local printer is a person with a press, not an upload form, and will ask for things print-on-demand never does. What to get from them first, what a shop is genuinely better at, and what it costs you.

Paper weight, opacity and show-through

Weight and opacity correlate but are not the same property, and opacity is the one that stops you reading page 47 through page 46. Print on demand picks the stock for you, so the useful knowledge is what to expect.

How print-on-demand actually works

A copy is manufactured when somebody orders it, on two different machines, and trimmed after it is bound. Once you know the sequence, most of the rules authors find arbitrary stop being arbitrary.

Books that need to lie flat

Cookbooks, workbooks, manuals and sheet music are used rather than read, and a perfect-bound spine springs shut. The binding options that solve it, what each one costs you, and how to design around it when your printer offers none.

Ordering author copies

How to buy copies of your own book from the printer, what the reduced rate does and does not cover, why shipping is the line that surprises people, and what to check the moment the box arrives.

Slipcases and boxed sets

A physical boxed set means a specialty printer, a minimum order and boxes in your house. What a slipcase is, how it is measured, why the spines are one canvas, and the cheaper things that do the same job.

Art books, photo books and oversized formats

Large formats cost more, ship in a different band and are not offered everywhere. What changes when the picture is the point: color range, paper, DPI at printed size, and what the gutter eats.

Moving a book to a different printer

Adding or changing a print-on-demand printer is a production job, not an upload. The interior usually travels unchanged; the cover almost never does, because every printer's paper bulks differently and the spine moves with it.

Printing a book with less waste

The honest environmental argument for a print-on-demand book is not the paper, which your printer chooses. It is that nothing is manufactured until somebody orders it, so there is no unsold stock to destroy.

Foil, embossing and other cover finishes

What spot gloss, soft-touch, foil, embossing and die-cutting actually are, why print-on-demand cannot do most of them, and what the files need if you take the route that can.

Endpapers, headbands and the parts of a hardcover

The case, the endpapers, the hinge, the headband, the rounded back and the gilt edge — what each part is, which of them you can actually specify at print-on-demand, and why printed endpapers are the upgrade a reader notices first.

Reading a print quote

What each line of a printer's quote means, what is deliberately not in it, and how to compare two quotes written in different house styles — because the cheaper one is usually a lighter paper rather than a better deal.

Holding stock, and shipping it yourself

Once you own boxes of books you have taken on a small warehouse and a small post room. What paper does in a damp garage, how to pack a book so it arrives sellable, and where the time actually goes.

The words printers use

A printer's spec sheet is the document that decides whether your files are accepted, and it reads like a foreign language the first time. Here are the terms, grouped by where you meet them, with what each one costs you if you get it wrong.

Why your proof and your production copies differ

An approved proof and a copy a reader received are not guaranteed to be identical. What legitimately varies between two copies, where the line sits between normal variation and a defect, and how to see what buyers actually get.