PDFs are a simple format for sharing documents online. From reports and contracts to manuals and policies, they are widely used because they preserve layout and look the same on any device.
However, while they may feel convenient, PDF accessibility is often overlooked and can harm both user experience and website performance.
In this guide, we’ll explore why this format isn’t always the best choice, how they compare to accessible alternatives, and what you can do to ensure your documents are usable for everyone.
What is a PDF?
PDFs (Portable Document Format) are one of the most common ways to share content online. Created by Adobe in the early 1990s, this format was designed to make sure a file looked the same no matter where it was opened. Unlike Word documents or web pages, a PDF essentially locks in the fonts, images, and layout so that the content always appears as intended.
Many organisations favour them because they are consistent, easy to distribute, and often considered a professional standard for official documents. For businesses looking for accessible web development for documents, however, HTML offers a far more inclusive and flexible approach.
Despite these benefits, they can create significant accessibility barriers. Although they can be made accessible, doing so requires 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 are PDFs bad for accessibility?
Accessibility is often overlooked when it comes to documents. Many PDFs completely miss the mark and are created without proper structure or tagging, making them difficult for assistive technologies like screen readers to interpret and putting users who rely on them at a disadvantage.
Some of the most common accessibility issues with this format include:
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Lack of semantic structure – Headings, lists, and tables are often missing or incorrectly applied, making navigation confusing.
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Images without alt text – Charts, diagrams, and graphics frequently have no descriptions, leaving out critical information.
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Poor colour contrast and small fonts – Text can be difficult to read, especially for people with low vision.
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No logical flow – Content may not be read in the intended order by a screen reader.
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Scanned documents – Image-only PDFs can’t be read by screen readers or searched for text.
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Inconsistent interactivity – Forms and interactive elements often aren’t designed to work with keyboards or assistive technologies.
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No document title or meta data – A proper title and description are crucial for screen readers to identify the document’s content and purpose.
These issues mean that, unless extra care is taken, this format can exclude large groups of users and create unnecessary barriers to accessing information.
What is an accessible alternative to a PDF?
The most accessible alternative is to publish content directly as an HTML page. Unlike static documents, HTML is designed to work seamlessly with assistive technologies and adapt to different devices.
HTML provides several advantages over PDFs, including:
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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.
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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.
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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.
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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. Learn more about how accessibility impacts SEO in our guide.
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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:
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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 are difficult to reproduce in HTML.
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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.
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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.
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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 PDF documents 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:
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Content remains up to date – Since the PDF is generated from the latest HTML content, there’s no risk of outdated documents floating around.
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Ensures accessibility – If accessibility features are built into the PDF generation process, elements like proper tagging, reading order, and alternative text will be preserved.
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Flexible formatting – PDFs can be tailored for readability, including larger fonts, simplified layouts, or high-contrast versions for users with visual impairments.
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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.
Why make PDFs 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.
Creating accessible PDF documents not only ensures compliance with standards like WCAG but also provides a better user experience for all.
Here’s what you need to do to ensure an accessible PDF:
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Use proper document structure – PDFs should have headings, lists, and proper reading order, just like a well-structured HTML page.
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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. Find out more in our guide on writing descriptive alt text for images.
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Ensure correct reading order – Many PDFs have text elements scattered in an illogical order, making them unreadable for assistive technologies.
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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.
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Provide proper contrast and font sizing – Users should be able to read content comfortably without excessive zooming.
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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. While the format has its place, relying on it too heavily can create barriers for those with disabilities and significantly disrupt the user experience.
If you’re serious about providing an inclusive experience, HTML should be the first choice whenever possible. It’s naturally more accessible, easier to maintain, mobile-friendly, and supports SEO.
That said, PDFs aren’t going away and may be required from time to time. When they are required, they must be created as accessible PDF documents, with proper structure, descriptive alt text, and compatibility with assistive technologies.
Better yet, consider implementing dynamic solutions that are automatically generated from an accessible website.
Don’t just pick and choose where to implement accessibility; take a holistic approach and become fully compliant across all your digital content.