A PDF (portable document format) is not a great format for sharing information online. Critical site content should be formatted using HTML, not presented in a PDF or other digital document format that needs to be downloaded and/or opened in another browser window to view.
Using PDFs to share information online presents several challenges:
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Difficult to read on mobile devices: PDFs are formatted for print, not for web viewing. They don't adjust to different screen sizes, making them hard to read on smartphones and tablets (requiring pinching and scrolling left and right). Worldwide browsing statistics show that more than 50% of online traffic is from mobile devices.
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Slow loading and accessibility issues: PDFs often contain large images and graphics, leading to bigger file sizes that load slowly. Ensuring these documents are accessible to all users can be complex.
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Quickly outdated: Updating information in a PDF is cumbersome. Uploading a new version can break existing links, and old versions may remain publicly available if not properly removed.
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Lower search engine rankings: While search engines can index PDFs, HTML pages are generally better for search engine optimization (SEO).
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Limited usage tracking: It's challenging to track how users interact with PDFs, as we can only monitor the number of times they're opened.
Creating accessible PDFs
In the cases where a document is included for downloading (i.e. for supporting documents such as minutes, letter templates, notices for printing and posting, or academic papers), it's best to use formats that don't require specific software to view. PDFs are recommended for this purpose.
To make PDFs accessible:
- specify the language attribute
- define the reading order
- apply alternative text to images.
- tag content according to semantic HTML standards
- ensure that all link text is descriptive
To learn more, see the Creating Accessible PDFs tutorial on the Accessibility Hub
Publishing a PDF to a web page
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Provide an executive summary of the document's content. This helps readers decide if they need to open or download it. If the document is a printable version of content already on the website, clearly inform your readers.
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Use descriptive link text and include details such as the file type and size, e.g., "Document Name (PDF 500 KB)".
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Enhance the link with icons to visually indicate a downloadable file, e.g.
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Ensure file names are descriptive to help users understand the document's purpose.
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Always include a publication date or version number within the document itself to provide context and indicate its relevance.
Referencing documents on other websites
When linking to a document or PDF hosted on another website, it's better to link to the web page that provides access to the document rather than linking directly to the PDF. This approach reduces the risk of broken links because document URLs often change when a file is updated, especially if the file name is altered during the upload process.