gitbook/docs/config.md

Configuration

GitBook allows you to customize your book using a flexible configuration. These options are specified in a book.json file. For authors unfamiliar with the JSON syntax, you can validate the syntax using tools such as JSONlint.

General Settings

Variable	Description
root	Path to the root folder containing all the book's files, except book.json
structure	To specify paths for Readme, Summary, Glossary etc. See Structure paragraph.
title	Title of your book, default value is extracted from the README. On GitBook.com this field is pre-filled.
description	Description of your book, default value is extracted from the README. On GitBook.com this field is pre-filled.
author	Name of the author. On GitBook.com this field is pre-filled.
isbn	ISBN of the book
language	ISO code of the book's language, default value is en
direction	Text's direction. Can be rtl or ltr, the default value depends on the value of language
gitbook	Version of GitBook that should be used. Uses the SemVer specification and accepts conditions like ">= 3.0.0"

Plugins

Plugins and their configurations are specified in the book.json. See the plugins section for more details.

Variable	Description
plugins	List of plugins to load
pluginsConfig	Configuration for plugins

Theme

Since version 3.0.0, GitBook can use themes. See the theming section for more details.

Variable	Description
theme	The theme to use for the book

Structure

In addition to the root variable, you can tell Gitbook where to find files for Readme, Summary, Glossary, Languages (instead of using the default paths such as README.md). These paths are relative to root of each book, and can be extended in every language's book.json.

Variable	Description
structure.readme	Path to the Readme file (defaults to README.md)
structure.summary	Path to the Summary file (defaults to SUMMARY.md)
structure.glossary	Path to the Glossary file (defaults to GLOSSARY.md)
structure.languages	Path to the Languages file (defaults to LANGS.md)

PDF Options

PDF Output can be customized using a set of options in the book.json:

Variable	Description
pdf.pageNumbers	Add page numbers to the bottom of every page (default is true)
pdf.fontSize	Base font size (default is 12)
pdf.fontFamily	Base font family (default is Arial)
pdf.paperSize	Paper size, options are 'a0', 'a1', 'a2', 'a3', 'a4', 'a5', 'a6', 'b0', 'b1', 'b2', 'b3', 'b4', 'b5', 'b6', 'legal', 'letter' (default is a4)
pdf.margin.top	Top margin (default is 56)
pdf.margin.bottom	Bottom margin (default is 56)
pdf.margin.right	Right margin (default is 62)
pdf.margin.left	Left margin (default is 62)