# Trim size

> Source: https://www.infinitelibrary.ai/glossary/trim-size

Last updated: 2026-09-06
Category: Typesetting & layout
Also called: Book size · Page size

Trim size is the finished width and height of a book’s pages after the edges are cut — 6 × 9 in and 5.5 × 8.5 in are the most common trade sizes.

## Definition

**Trim size** is the final page dimension of a printed book, stated width × height. Books are printed on larger sheets and then trimmed on three sides, which is why the size is named for the cut and why **bleed** exists.

The common North American trade trims are **5 × 8, 5.5 × 8.5 and 6 × 9 in** for novels and nonfiction, 8.5 × 11 in for workbooks and manuals, and squares such as 8.5 × 8.5 in for picture books and photo books. UK and European trade sizes are B-format (129 × 198 mm), A-format (110 × 178 mm), demy (135 × 216 mm) and royal (156 × 234 mm).

Trim size is the first typesetting decision because everything else depends on it: a 90,000-word novel is about 340 pages at 5.5 × 8.5 in and nearer 300 at 6 × 9 in, which changes the spine width, the printing cost and the price.

## In Bindery

Bindery’s 21 print presets cover the standard trade trims — 6 × 9, 5.5 × 8.5 and 8.5 × 11 in among them, plus 8.5 × 8.5 in square for picture books — and the spine is sized from the page count at that trim.

## Related

- [Bleed](https://www.infinitelibrary.ai/glossary/bleed)
- [Margins](https://www.infinitelibrary.ai/glossary/margins)
- [Spine width](https://www.infinitelibrary.ai/glossary/spine-width)
- [Word count](https://www.infinitelibrary.ai/glossary/word-count)
- [Casewrap hardcover](https://www.infinitelibrary.ai/glossary/casewrap-hardcover)
- [Hardcover Memoir Maker](https://www.infinitelibrary.ai/formats/hardcover-memoir-maker)
- [Children's Picture Book Maker](https://www.infinitelibrary.ai/formats/childrens-picture-book-maker)
- [Lie-Flat Recipe Book Maker](https://www.infinitelibrary.ai/formats/lie-flat-recipe-book-maker)
- [Book Publishing Glossary — 59 Terms Defined](https://www.infinitelibrary.ai/glossary)
- [Bindery — the Claude-powered book studio](https://www.infinitelibrary.ai/bindery)

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