Why PDFs can be problematic for accessibility
While PDFs can be made accessible with the right tools and techniques, they are inherently more complex and challenging to navigate than HTML content. Here’s why PDFs can pose problems for accessibility:
- PDFs are often not fully compatible with screen readers and other assistive technologies, especially if they are not properly tagged or structured. This can make it difficult or impossible for people with visual impairments to access the content.
- PDFs do not always offer the same ease of navigation as web pages. People may struggle to find specific information within a PDF, especially if it lacks proper headings, bookmarks, or a logical reading order.
- PDFs are typically designed with fixed layouts, making them difficult to read on smaller screens or mobile devices. Unlike HTML content, PDFs do not automatically adapt to different screen sizes, which can create a poor user experience.
- Many PDFs do not allow users to easily adjust text size or reflow text
- Unlike HTML content, which can be easily edited and updated, PDFs often require specialized software and expertise to modify. This can lead to outdated or inaccessible content being left online.
Best practices for avoiding PDFs and providing accessible alternatives
To ensure your content is accessible to the widest possible audience, consider the following best practices:
Use HTML whenever possible
HTML content is generally more accessible and user-friendly than PDFs.
- HTML is naturally responsive, meaning it adjusts to different screen sizes and devices. This ensures that your content is readable and navigable on desktops, tablets, and smartphones.
- HTML is compatible with screen readers and other assistive technologies. When properly structured, HTML allows users to navigate through headings, links, and other elements with ease.
- HTML content can be easily updated and maintained, ensuring that your information remains current and accessible.
See WCAG 2.4.5: Multiple Ways for additional details.
Convert PDFs to HTML content
If you already have content in PDF format, consider converting it to HTML.
- For simple documents, you can manually copy the text and images from the PDF and format them in HTML. Be sure to add appropriate headings, alt text for images, and other accessibility features.
- There are tools available that can help convert PDFs to HTML, but be aware that these may not always produce perfect results. Manual review and editing will likely be needed to ensure the content is accessible.
Create accessible PDFs if necessary
If you must use PDFs, take steps to ensure they are as accessible as possible.
- Use PDF authoring tools that allow you to add tags, headings, and a logical reading order to the document. This helps screen readers navigate the content more effectively. See WCAG 2.1.1 Keyboard.
- Include alt text for images, graphs, and other visual elements in the PDF to ensure that all users can access the information.
- Ensure that the text in the PDF is easy to read by using accessible fonts and colors with sufficient contrast. Avoid using images of text, which cannot be read by screen readers.
- Use tools like Adobe Acrobat’s accessibility checker to identify and fix potential accessibility issues in your PDF. Also, consider testing the PDF with a screen reader to ensure it’s usable for people with visual impairments.
Offer multiple formats
When providing important information, consider offering it in multiple formats to accommodate different user needs.
- Whenever possible, prioritize HTML as your primary format. This ensures the content is accessible by default.
- If a PDF is necessary, offer it as a secondary option alongside the HTML version. Clearly indicate that the HTML version is available for those who prefer a more accessible format.
- For simple documents, consider offering a plain text version, which can be easily read by screen readers and is accessible on all devices.
Educate and advocate for accessibility
If your organization frequently uses PDFs, consider advocating for a shift towards more accessible formats.
- Provide training for colleagues and stakeholders on the importance of web accessibility and the challenges associated with PDFs. Offer guidance on creating accessible content and alternatives to PDFs.
- Work with your team to develop policies that prioritize accessible content formats and reduce reliance on PDFs. This might include guidelines for when PDFs are appropriate and how to ensure they are accessible.
Examples of accessible alternatives to PDFs
To illustrate how you can replace PDFs with more accessible formats, here are some examples:
- Instead of providing a report as a PDF, publish it as an HTML page with sections divided by headings and subheadings. Include a downloadable PDF version for users who need it, but emphasize the HTML format as the primary option.
- Convert PDF forms to HTML forms, which are more accessible and easier to fill out on various devices. Ensure that form fields are properly labeled and that the form can be navigated using a keyboard.
- Publish manuals or guides as a series of web pages, each covering a different topic or section. Use a table of contents with links to each section, making it easy for users to navigate.
If you must use PDFs, make them as accessible as possible
We have a guide to making PDFs accessible (Article – PDF accessibility – a practical guide), along with a full webinar on PDF accessibility, which we’d encourage you to read or watch.
While PDFs can be useful in certain situations, they often pose significant accessibility challenges. By prioritizing HTML and other accessible formats, you ensure that your content is available to the widest possible audience, including users with disabilities.