iA / Writer / Support / Preview

Custom Templates

Preview, create PDFs, and print documents in your own style with templates in iA Writer.

Templates are built with web pages. You can use HTML, CSS, and JavaScript to lay out your documents. If you know how to make a website, you can easily make an iA Writer template.

iA Writer templates are bundles: directories that group template files together. Bundles are natively supported by macOS and iOS. To browse template contents, right-click it in Finder and choose “Show Bundle Contents”.


Installing Templates

You can download our sample template (iatemplate) from GitHub.


Note: Template bundles are copied when installed. Any changes made to the original bundle will not be visible in iA Writer. You may modify the installed bundles. To find an installed bundle, right-click one in Preferences and select “Show in Finder”.


iOS supports adding template bundles, as well as ZIP archives, with one template per archive.

Windows (v. 1.2+)

Download the template then, from iA Writer’s menu choose: FileInstall Template → Select ‘TemplateName.iatemplate.zip’ file.

The Template Folder

HTML Files

iA Writer templates use separate HTML files for laying out the title page, document text, headers, and footers.

Template Properties

Template pages and other properties are defined in Info.plist. We recommend starting with our example bundle if you’ve never dealt with property list files before. XML property list files can be edited in any text editor.

Key Value Presence Description
CFBundleName String Required Template name shown in iA Writer.
CFBundleIdentifier String Required Uniquely identifies1 a template.
IATemplateDocumentFile String2 Required Lays out document text.
IATemplateTitleFile String2 Optional Lays out a title page on export.
IATemplateHeaderFile String2 Optional Draws at the top of each document page on export.
IATemplateFooterFile String2 Optional Draws at the bottom of each document page on export.
IATemplateHeaderHeight Number Optional Header height, in CSS pixels (≤400).
IATemplateFooterHeight Number Optional Footer height, in CSS pixels (≤400).
IATemplateDescription String Recommended A sentence that describes your template.
IATemplateAuthor String Recommended A person (or a company) who created the template.
IATemplateAuthorURL String Recommended A link to template’s author.
IATemplateSuportsSmartTables Boolean Optional Whether to process Smart Tables. Defaults to YES if absent.
IATemplateSupportsMath Boolean Optional Whether to process TeX math expressions into MathML. Defaults to YES if absent.
IATemplateTitleUsesHeaderAndFooterHeight Boolean Optional When set to NO changes header and footer height on title page to 0. Defaults to YES if absent.
  1. iA Writer uses the bundle identifier to associate templates with documents. Each template must have a unique identifier. The identifier must contain only alphanumeric (A-Z, a-z, 0-9), hyphen (-), and period (.) characters. The string should be in reverse-DNS format. For example, if your company’s domain is example.com you could assign the string com.example.template as the bundle identifier.
  2. HTML file name, without path extension. The actual files themselves must have an html extension.


iA Writer applies content to HTML using JavaScript. It replaces innerHTML on elements with several predefined data attributes.

For example, <span data-date></span> becomes <span data-date>June 22, 2016</span> when a page is loaded for export.

iA Writer dispatches an ia-writer-change event to elements when it updates them with new content.


The document page lays out the text from the editor in Preview, printed documents, and PDFs.

Attribute Description
data-document Document text as HTML.

iA Writer uses MultiMarkdown (with a few additions) to convert Markdown to HTML. Markup.txt contains some of the most commonly used markup in iA Writer. Markup.html is the resulting HTML for data-document.

Title Page, Header and Footer

Title page, header, and footer are used only in in printed documents and PDFs.

Attribute Description
data-page-count Total page count of the exported document.
data-page-number Current page number.1
  1. data-page-number is not available in title pages. They do not have a page number to keep numbering the same whether or not you include the title page during export.

All Pages

Attribute Description
data-title Document title, taken from document file name.
data-author Document author, if specified in Preferences.
data-date Current date. You can specify date format1 in the attribute value: data-date="MMMM yyyy". Date format patterns are described in Unicode Technical Standard #35. On Windows, Microsoft standards are used.
  1. data-date output may not contain exactly those components given in the attribute value, but may—for example—have locale-specific adjustments applied: yMMMMd may become MMMM d, y in the US, and d MMMM y in the UK.


We recommend all template authors spend a few minutes to make their templates look great in Preview by adding support for night mode, as well as system-wide font size on iOS.

iA Writer uses the class attribute of the <html> element for environment data. Avoid adding custom classes to this element, because they will be replaced when a template is loaded.

Class Description
night-mode Night mode is active.1
ios Preview on iOS.2
mac Preview on macOS.
  1. Note that users may invert night mode in Settings on macOS.
  2. We strongly recommend using standard media queries to make your templates responsive. However, sometimes it’s important to differentiate between iOS and macOS. For example, default templates have a slightly different color scheme on each platform.

Developing Templates

To fully reload the currently visible template in Preview on macOS, press Shift Command R.

To enable Web Inspector in Preview, paste the following command into Terminal.

defaults write pro.writer.mac WebKitDeveloperExtras -bool true

On Windows, you can enable the Chromium inspector by using Ctrl J.

Vertical Margins

Avoid vertical margins and padding for the document page.

Toolbar Color

iA Writer adjusts Preview toolbar colors to match the currently visible template on macOS. Be sure to set color and background-color on the <html> element.

Font Size on iOS

iA Writer supports system-wide font size on iOS. Users can adjust the font size in Settings > Display & Brightness > Font Size. Most templates should adjust font size for this setting.

Class Description
content-size-xs An extra small font.
content-size-s A small font.
content-size-m A medium-sized font.
content-size-l Default value. A large font.
content-size-xl An extra large font.
content-size-xxl An increasingly large font.
content-size-xxxl The largest font option.

Note that some users may enable accessibility sizes in Settings > General > Accessibility > Larger Text.


Contact Us

If you are experiencing a problem that our support section doesn’t solve please reach out to us. We take a break on the weekends (JST), but during weekdays we aim to reply within 1-2 business days.


Modify the Preview

To see your formatted text and to change its look, open Preview.

Export Share Print

Learn how to export, share and print your documents


Preview, create PDFs, and print documents with iA Writer's templates.

Custom Templates

Create iA Writer templates in your own style.


How to to draft blog posts before uploading them to your website.