Author Toolkit · Free tool

Interior Layout Calculator

Get the correct margins, gutter and bleed for the inside of your book, so text never gets swallowed into the spine or trimmed off the edge.

Your interior

Trim size

Page count

My interior has images or colour running to the edge (full-bleed) Leave unchecked for a text-only interior, it usually needs no bleed.

See it to scale As you change the trim size, this shows the book's real shape and relative size, the dashed area is your text (inside the margins & gutter).

Choose a trim size to preview it.

Book edge (trim)Text area (inside margins)

Set your document up like this

Your interior spec

Page size—

Inside margin (gutter) scales with page count—

Outside / top / bottom—

BleedNone

Enter your trim size and page count to see your interior setup.

Which spec is this? These recommendations use the Amazon KDP model, the anchor platform. Minimum margin and gutter rules differ slightly on IngramSpark and other printers, and they grow with page count. OW always checks and adjusts final files before upload.

Optional

Send these specs to OW

Want us to format your interior to this spec? Send your setup and we'll take it from here.

Your calculated specs, sent with this form

Page size—
Page count—
Inside (gutter)—
Outside / top / bottom—
Bleed—
Interior type—

Name *

Email *

WhatsApp *

Book title

Software you'll use

When do you need it?

Notes for formatting

We use your details only to prepare your formatting quote.

Got it, your interior specs are in

We'll be in touch about formatting your interior. Prefer to chat? WhatsApp us.

The companion tool

Need your cover size too?

The Cover Template Calculator gives you the exact spine width and full-wrap canvas for your cover.

Open the Cover Calculator → Back to Self-Publishing