PDFs (Portable Document Format) are widely used for sharing content on websites, often seen as a convenient and universal format. However, whilst they work across different software, hardware, and operating systems, they frequently create accessibility barriers and result in poor user experiences.
Whilst PDFs can be made accessible, they require extra effort. More often than not, they are published without accessibility in mind, making them difficult or impossible to use for people with disabilities.
Why HTML is Better Than PDFs
If content can be published as an HTML page, it should be. HTML provides several advantages over PDFs, including:
- Better Accessibility – Screen readers, keyboard navigation, and assistive technologies handle HTML much more effectively than PDFs. Many PDFs lack proper tagging, reading order, or meaningful structure, making them difficult to navigate.
- Responsive Design – HTML adapts to different screen sizes, ensuring content is readable and usable on mobile devices, tablets, and desktops. PDFs, on the other hand, are often fixed-width and require zooming and panning to read on smaller screens.
- Easier Updates & Maintenance – Updating an HTML page is straightforward and doesn’t require re-uploading a new document. PDFs, however, require editing in external software, exporting, and replacing old versions. This leads to outdated documents lingering on websites.
- SEO & Discoverability – Search engines can index HTML pages more effectively than PDFs. Whilst PDFs can be optimised for search, they don’t integrate with website navigation or internal linking as seamlessly as HTML.
- Lower Cognitive Load – PDFs interrupt the natural flow of website browsing. Users must download or open a separate document, breaking their experience and making navigation more cumbersome.
If you’re using PDFs simply to display content that could work as an HTML page—such as articles, reports, policies, or instructions—it’s time to rethink your approach.
When PDFs Might Be Necessary
That said, there are a few valid use cases for PDFs where HTML may not be the best option:
- Technical drawings and complex layouts – Some industries require documents with precise formatting, such as engineering schematics, architectural plans, or legal contracts. These often need to be print-ready and difficult to reproduce in HTML.
- Forms that require completion and signatures – Whilst web forms are generally a better choice for accessibility and usability, some legal and administrative processes still require downloadable PDFs for signing.
- Documents meant for annotation – Many students, researchers, and professionals rely on PDFs for taking notes, highlighting, and annotating. Some workflows still depend on downloadable and editable documents.
- Long, structured documents – Whilst HTML can work well for lengthy content, some users prefer to download and read structured documents like white papers, reports, and manuals offline.
If your document falls into one of these categories, PDFs might be appropriate—but they must still be accessible.
A Better Alternative: On-Demand Accessible PDFs
Instead of relying on pre-made, static PDFs, websites can be designed to dynamically generate accessible PDFs on demand. This allows content to be published as HTML (ensuring accessibility, responsiveness, and easy updates) whilst still offering users the ability to download a well-structured, accessible PDF version.
This method requires special programming, but it offers several advantages:
- Content remains up to date – Since the PDF is generated from the latest HTML content, there’s no risk of outdated documents floating around.
- Ensures accessibility – If accessibility features are built into the PDF generation process, elements like proper tagging, reading order, and alternative text will be preserved.
- Flexible formatting – PDFs can be tailored for readability, including larger fonts, simplified layouts, or high-contrast versions for users with visual impairments.
- User-friendly experience – Visitors get the best of both worlds: an accessible online experience and a downloadable document if needed.
For organisations that need PDFs but also want to maintain an accessible website, dynamic PDF generation is a smart compromise.
If You Must Use PDFs, Make Them Accessible
If a PDF is truly necessary, it must be created with accessibility in mind. Unfortunately, most PDFs published online fail even basic accessibility checks.
Here’s what you need to do to ensure an accessible PDF:
- Use Proper Document Structure – PDFs should have headings, lists, and proper reading order, just like a well-structured HTML page.
- Add Alternative Text to Images – Any meaningful images, graphs, or charts must include alternative text descriptions so that screen reader users can understand their content.
- Ensure Correct Reading Order – Many PDFs have text elements scattered in an illogical order, making them unreadable for assistive technologies.
- Enable Text Selection and Search – Avoid scanned PDFs, which are essentially just images of text. If a PDF contains text, it must be selectable, searchable, and readable by screen readers.
- Provide Proper Contrast and Font Sizing – Users should be able to read content comfortably without excessive zooming.
- Test with a Screen Reader – Just because a PDF looks fine visually doesn’t mean it’s accessible. Testing with assistive technologies ensures real usability.
The Bottom Line
Many organisations default to PDFs without considering their impact on accessibility and usability. If you’re serious about providing an inclusive experience, HTML should be the first choice whenever possible.
When PDFs are required, they must be created accessibly—or better yet, dynamically generated from an accessible website.
