Making Your PDFs Accessible: A Complete Guide

PDF accessibility ensures that your documents can be read and understood by everyone, including people who use screen readers, have visual impairments, or have other disabilities. It's not just good practice — in many jurisdictions, it's a legal requirement.

Why PDF Accessibility Matters

• Inclusivity: Over 1 billion people worldwide have some form of disability.
• Legal compliance: Laws like ADA (US), Section 508, and EN 301 549 (EU) require accessible documents.
• Better UX: Accessible PDFs are better structured and easier for everyone to navigate.
• SEO benefits: Well-structured, tagged PDFs are better understood by search engines.

Key Elements of an Accessible PDF

1. Document Tags

Tags define the structure of your PDF — headings, paragraphs, lists, tables, and images. They're essential for screen readers to navigate the document.

Think of tags as the HTML of your PDF. Just as a web page uses <h1>, <p>, and <ul> tags, a PDF uses similar tags to define its structure.

2. Alternative Text

Every image, chart, and non-text element should have descriptive alt text that conveys the same information to users who can't see the visual content.

Good alt text: "Bar chart showing quarterly revenue growth from $1.2M in Q1 to $2.1M in Q4" Bad alt text: "Chart" or "image1.png"

3. Reading Order

The logical reading order should match the visual layout. Screen readers follow the tag order, so it must make sense when read linearly.

4. Language Specification

Set the document's language so screen readers use the correct pronunciation and grammar rules.

5. Bookmarks and Navigation

Long documents should include bookmarks that mirror the heading structure for easy navigation.

6. Color Contrast

Ensure sufficient contrast between text and background colors. The WCAG 2.1 standard requires a minimum contrast ratio of 4.5:1 for normal text.

Creating Accessible PDFs

The best approach is to start with an accessible source document:

1. Use heading styles (H1, H2, H3) instead of just making text bigger or bold.
2. Add alt text to all images in your source document.
3. Use proper table structures with header rows and columns.
4. Set the document language in your word processor.
5. Use meaningful link text instead of "click here" or raw URLs.

Testing Accessibility

Several tools can help you check your PDF's accessibility:

• Adobe Acrobat Pro: Built-in accessibility checker
• PAC (PDF Accessibility Checker): Free, detailed testing
• NVDA or VoiceOver: Test with actual screen readers

PDF/UA Standard

PDF/UA (Universal Accessibility) is the ISO standard for accessible PDFs. It requires:

• All content must be tagged
• Tags must reflect the logical reading order
• All images must have alt text
• Document language must be specified
• Security settings must not interfere with assistive technology

Learn more about archival standards in our PDF/A Archival Guide.

Conclusion

Creating accessible PDFs is both an obligation and an opportunity. By following these guidelines, you ensure your documents reach the widest possible audience while meeting legal requirements. SublimePDF is committed to supporting accessible document workflows in all our tools.