PDFs Aren’t Ideal for SEO – Should You Still Try to Optimize?

Why PDFs Aren’t Ideal for SEO

I get it. Your campaign or digital marketing team wants a PDF file to promote, so you find yourself having to create a slew of them. As a content marketing strategist, I used to call these PDFs (usually white papers, case studies, ebooks, guides, or data sheets) Big Rocks.

As content efforts go, they required significant effort, dominated production schedules, and they had to be done by a given date. They also were a giant rock on your SEO traffic. We’d put all this effort into a content asset — and then people would be upset that aside from a few specific PDFs, the HTML pages didn’t generate much organic traffic.

But does this mean you should stop using PDFs altogether? Should you stop trying to optimize them? Not necessarily. As with so many things in marketing — it depends. Here’s what you need to consider.

What Is a PDF?

A PDF file, or Portable Document Format File, is an ideal format for creating and sharing content to any device via a web browser. Think of it as a container that holds text, images, tables, links, audio, video, and forms. Created over 30 years ago by Adobe, it’s become a go-to for sharing text, images, links, tables, and even multimedia content.

PDFs offer full control over branding elements like layout, fonts, and colors, making them appealing to marketers. You can lock the PDF document down with a password, and it isn’t easy to change so the format stays consistent. It also is an ideal format if you want to share a ton of text — like a book or report.

As a container, the document’s properties — or the metadata associated with a PDF-are about the administrative information in the document itself: when it was created, subject, title, owner. You can also add metadata like keywords, topics, etc.

Like any content, a PDF can be crawled and indexed by a search engine like Google by transforming the PDF into an HTML page. Although it will tag it as a PDF on the search engine page results (SERP).

However, unlike HTML pages, PDFs require additional effort to prep for search engine optimization.

Why PDFs Are Challenging for SEO

While PDFs can be indexed by search engines, they lack many advantages of HTML web pages. Here’s why PDFs tend to struggle with SEO:

1. Limited Metadata
2. PDFs often lack the proper metadata (e.g., title tags, alt text) that Google relies on to assess relevance. Without this, search engines default to using file names or other less descriptive elements, which impacts click-through rates.
3. No Hierarchical Structure
4. Unlike HTML, PDFs don’t inherently communicate the hierarchy of content. Search engines can’t interpret font size or stylization to determine the importance of headings or keywords. This limits how well PDFs can be optimized for keywords.
5. Poor User Experience
6. PDFs are often not mobile-friendly, requiring users to download the document. This creates friction and contributes to a subpar user experience, which search engines like Google penalize.
7. Link Equity Limitations
8. Links within PDFs don’t pass authority in the same way as links on web pages. This limits their effectiveness as part of an internal linking strategy.
9. Analytics and Tracking Gaps
10. Standard analytics platforms like Google Analytics struggle to track PDF engagement. Since PDFs don’t trigger pageviews, they often represent a “dead end” in user journeys.

Can You Optimize PDFs for SEO?

As noted, you certainly can optimize PDFs for SEO. It’s not quite as easy as an article page, and here’s why — and this has to do with the inherent file format and the overall user experience.

An article or blog post is created in HTML, or HyperText Markup Language. It’s a code that defines the structure and meaning of a web page’s content. The tags used not only convey how something should be displayed, but they relay to the search engine the hierarchy of importance. A topic being used in an <H2> tag is showing the importance of that word.

Conversely, search engines don’t directly understand the “tag size” in a PDF format, meaning they won’t prioritize content based on the font size of headings or text within the tags. Many times, too, a designer might want to emphasize a given word or phrase by putting the word in a stylized font, in a different color, and at a larger size. The search engine can’t pick up on these cues. You’d need to explicitly call out the headings using the property feature.

There’s another reason PDFs tend not to rank well. Search engines like Google are trained to focus on providing a great user experience. Anyone using a mobile phone is going to hate the idea of downloading a PDF. Therefore, PDF content immediately falls into the bucket of “not a great experience.”

I searched Optimizing for SEO — and there are no PDFs on the first few SERP pages of Google search. Instead, Google calls out PDF optimization specifically in the nav bar at the bottom of the SERP.

When Should You Use PDFs?

There are times when PDFs are the right choice, despite their SEO drawbacks. Examples include:

• Annual or Industry Reports: Highly detailed, data-rich documents intended for download and offline use.
• Case Studies or Research Papers: Long-form assets where the format itself adds perceived value.

Books or Guides: Comprehensive content designed for distribution.

Usually the PDF itself is sought out for research or evidence-building purposes. People want to be able to download the information and pass it on to others or save them to make reference to them at a later time. In these cases, the user experience aligns with the intent of downloading a PDF.

These types of content should be optimized for their environment — and not about given topics. Here’s what I mean by that.

At Coveo, an AI-Powered search company for enterprises, we created annual relevance reports for a variety of key industries.

Instead of aiming to rank for the topics covered within the report, we optimized for the report itself. We had branded the report as the [year] Coveo Relevance Report for [given sector]. We then created a dedicated landing page for the report, rich in keywords and metadata. This page included:

• A summary of the report’s key findings.
• Keywords around the date and name of the report to capture organic search traffic.
• Links from related blog posts and relevant content clusters that drove traffic to the landing page.

• The name of the report in the URL, title tag, and meta description.

A press release goes out to the media announcing this asset. The press release has a link to the asset — so any media mentions will also include that link. The media is branding the report as the 2023 Relevance Report — so people will search for it.

By structuring the content around the PDF, Coveo ensured the report gained visibility while offering users an intuitive way to access it.

Of note. These annual reports had a date associated with them — the 2023 report, 2024, etc. Our policy wasn’t to overwrite these reports. Since the media used them, we wanted to make sure the report was available for reference. Therefore, the date was in the URL.

Other PDFs, like a Guide to Search — didn’t have dates — as we updated them regularly.

This approach highlights an important lesson: the SEO value of a PDF lies not in the document itself but in the ecosystem of HTML content built around it.

How to Optimize PDFs for SEO

If you must use PDFs, here are some best practices to improve their performance:

1. Optimize Metadata
2. Use tools like Adobe Acrobat to ensure the PDF title, subject, author, and keywords are populated with relevant, descriptive text.
3. Include Search-Friendly Text
4. Use Optical Character Recognition (OCR) to ensure text is readable by search engines. Avoid embedding text in images or using decorative fonts.
5. Add Links Thoughtfully
6. Include relevant internal and external links in the PDF. While not as effective as HTML links, they still provide some value.
7. Compress and Optimize for Mobile
8. Ensure the file size is manageable and the document is legible on smaller screens.
9. Set Canonical Tags
10. If the PDF duplicates content available on a web page, set a canonical tag pointing to the HTML version to avoid duplicate content issues.

Building a Content Strategy Around PDFs

Instead of focusing solely on optimizing PDFs for SEO, determine why you are using that format as part of a broader content strategy:

• User-Centric Purpose for PDFs — Consider why you are using a PDF format. Is it the best format from a user’s perspective? If so, as in the Coveo example above, make sure that the asset title is prominent in the URL, the metadata description, and the title tag.
• Create Landing Pages — Use dedicated landing pages to promote PDFs. These pages can be optimized for SEO, driving organic traffic and encouraging downloads.
• Break Down Content — Repurpose PDF content into blog posts, infographics, or other formats that can rank better in search engines. These are the pages that should be optimized for SEO!
• Leverage Content Clusters — Surround the PDF with a cluster of related content, linking back to the landing page or the PDF itself.

Analyze and Improve — Regularly audit your PDFs to identify those ranking well for relevant intents. If a PDF ranks for an important query, consider creating a web page to replace it.

Summary

PDFs can be a valuable tool for specific content needs, but they need to be strategically used as they can be inherently challenging for SEO. When using PDFs, it’s important to recognize their limitations and design your content strategy accordingly. Instead of trying to make SEO-friendly PDFs, focus on supporting them with optimized landing pages, content clusters, and repurposed material.

By following these strategies, you can ensure your PDFs contribute to your marketing goals without sacrificing SEO performance.