PDFs: What are they good for?
PDFs are commonly used for sharing information and documents, but they have limitations and drawbacks that make them less than ideal for use on the web, especially when compared to good old HTML. But take a quick look around the internet and you’ll find PDFs on all sorts of websites. We quickly found a bunch of examples:
- Government documents such as proposed bills on the US Congress website
- Press releases
- Restaurant menus
- Product brochures and data sheets
- Investor relations reports
- Even the Department of Justice’s recent Section 508 report on federal government digital accessibility performance
PDFs are great at providing a defined and consistent print layout. When your audience downloads and print a PDF, you can be sure that the document they read is identical to any other.
It’s also understandable that content managers regularly share information on their sites in PDFs. From a web editor’s perspective, the decision seems easy. The content is already created, formatted and approved by the original content creator. And you can have 100% confidence that everyone will see the exact same thing. So why not just put it up there?
In our experience, the experience of reading PDFs on the web is poor. Here’s why we think so.
PDFs are not responsive
These days, just about all websites are naturally mobile-friendly with layouts automatically resizing and content reflowing to fit the current screen size. But PDFs are optimized for print layouts which are inherently static. Even when a user is able to open a PDF on their mobile device, the layout will not flex. And this regularly presents usability issues on mobile. Users can zoom in order to better read content, but that requires the user to scroll both horizontally and vertically in order to see everything.
But this limitation also applies to many users on desktop browsers or readers. Visually impaired users who rely on magnification or zooming in order to read content can have a difficult time when attempting to read a PDF without bi-directional scrolling.
PDFs required context switching
While most desktop browsers can open PDFs by default, links to a PDF take the user away from the website. At minimum, this is a drag on engagement as the user will have to close the PDF to return to the site. But it can also be a usability concern as the PDF might open in a different application or even just a different browser tab. The user no longer has access to your site navigation and the page is organized completely differently from how it would be on your website. And even the back button may not work.
Technical accessibility issues in PDFs
HTML is inherently accessible.
Of course, it’s quite possible to design or code an inaccessible experience anyways. But PDFs start off as inherently inaccessible. The experience is linear with no navigation or semantic heading organization. The user is forced to start from the very beginning of the document and make their way through until finding what they need.
Adding a clickable table of contents with anchor links is not sufficient either. If the user doesn’t find what they want, they have to scroll all the way back to the beginning to try again.
Within the document, there are steps that you can take to tag headings, images, and other content with the appropriate metadata to be usable for screen readers. But this is an extra step that needs to be taken on each PDF file. And it’s unlikely that the original PDF creator has the necessary knowledge to take these steps on their own.
PDFs make it harder to achieve digital objectives
While PDFs create a poor and inaccessible user experience, there are other reasons why you should be wary of using PDFs unnecessarily. They can also stand in the way of your organization’s digital goals by making it harder to gather analytics, manage content assets, and rank for SEO.
- Not trackable: Site owners can learn a tremendous amount about how people engage with their web content including link clicks, time spent on page, and other custom tracking events. For PDFs, you can track how many people downloaded the file. That’s it. There is no easy way to know if anyone is even reading it, let alone more granular engagement data.
- Slow pagespeeds: As a site owner, optimization of page load performance is within your control. Not so with PDFs. Each file needs to be optimized individually; simply uploading a PDF is not necessarily the simple option when you need to figure out how to reduce the size by 20MB.
- PDFs are easy to upload but hard to update: All of the reasons why content editors find it easy to upload a PDF to their site make it harder to keep the content up to date. Without having the original document used to generate the PDF, it’s not possible to update content or copy. You are dependent on the PDF owner to make updates or let you know that the information is no longer valid.
- PDF URLs are not evergreen: Even if you manage to keep all of your PDF content up to date, that doesn’t mean the old file is not still floating around there. If you don’t make use of version controlled asset management or keep track of redirects, it’s likely that visitors will still reach the out-of-date PDF content or get stuck at a 404 error when using a bookmarked URL or clicking on organic search result links.
Building usability into your PDF flow
It’s not possible to completely eliminate PDFs tomorrow, but there are some questions and steps you can take into account to reduce and mitigate usability and accessibility challenges around PDFs.
- Consider whether a PDF can actually be a webpage: Limit your use of PDFs to content that is primarily meant to be printed.
- Create HTML alternatives: Even if a PDF version of content is necessary, that doesn’t mean it needs to be the only way to consume a piece content. Provide an equivalent (and accessible) web-based version and let the user choose what works best for them.
- Generate or remediate for accessibility: When you must publish a PDF, make sure that it is properly tagged with semantic metadata for screen readers and other assistive technologies.