SEO for PDFs

We are often asked if PDFs are included in search engines. They are definitely searchable, but they are often not indexed because they aren’t optimized. This means that the search engines skip them when they spider your site because they don’t know what the content is about.

It is better to put your content in a regular web page, but if you want to post a PDF, and there are many reasons to do this, then here are the steps to optimize your PDF that will help search engines to index the content.

When are PDFs the Best Type of Content?

1. If a PDF is already on your site and there are many links to it from other websites.

2. A PDF is a great option if the material is designed with a specific look that wouldn’t translate well to HTML.

3. If the content is something you want visitors to print or download for later use. For example, a newsletter, book, brochure, product sheets, manuals or forms meant to be printed and filled out by hand.

Here is a description on how to optimize your PDFs.

Tip 1: Always Use Text-Based PDFs

Search engines understand text better than images (though the engines do have rudimentary optical character recognition capabilities), so make sure the words in your PDF are basic copy-and-pasteable text, not pictures of words. Most of the big PDF creators, like those in Adobe Creative Suite, will automatically make text-based PDFs.

If you have a scanned document you want to optimize, you’ll need to run Optical Character Recognition (OCR) software on the document to turn it into text. Be careful because OCR isn’t foolproof and can have many errors in the text after conversion. Best option here would be to recreate it in HTML or make a new PDF.

Tip 2: SEO for PDFs – Set Title and Description Tags

The title tag is very important for search engine ranking. To add a title tag to a PDF, you will need to open the document and set the document properties. Almost all PDF creators support this functionality, including Adobe applications such as InDesign. You want to smartly utilize keywords and optimize your title tags.

Tip 3: Set an SEO-Friendly URL (Filename)

The PDF filename will become part of the URL (the web address to the document). Additionally search engines often use the URL as part of the title tag even if the title is set. It is important to keep this in mind when you save the file. Make sure it is keyword rich. This is an example of a file that doesn’t have the title set, no one, including Google, knows what this document is about.

Tip 4: Use SEO Best Practices

SEO for PDFs best practices are the same as those for regular pages. Follow your other usual SEO best practices to optimize your PDFs as well. This includes:

  • Linking to the PDF document on your website from other pages on your website will give the PDF some authority. Additionally, you should link from the PDF to other pages on your website when relevant. It helps your SEO efforts and the user experience.
  • Good Keyword selection is important. Make sure your keyword phrase is relevant to the content on your page, and use the Google Keyword selection tool for suggestions based on the content of your page. Here is a guide to keyword selection.
  • Make sure Keywords are in your body copy.
  • Image optimization: If you have images in your PDF, you can set alt tags (descriptions of the images using keywords) that will help the search engines scan the content.
  • Good Content is Good Optimization.

Tip 5: Keep PDF file size small

Huge files load slower, which affects user experience and the search engines’ crawl. Adobe has the “PDF Optimizer” function, which will allow you to reduce file size, and you’ll want to use it for heavy PDFs.

Tip 6: Avoid duplicate content

Having both HTML and PDF versions of the same content can sometimes be a wise choice, but only if you take measures to prevent the duplicate content issue. Also, if you tweak a PDF and re-upload it, don’t create a duplicate by accidentally changing the filename and changing the URL.

In summary, just follow this SEO for PDFs checklist:

  • Always use text-based PDFs
  • Set your title, description, and keywords in the document properties
  • Select an SEO-friendly URL/filename
  • Select relevant keywords
  • Keep the file size as small as possible
  • Avoid duplicate content


Posted by Suzanne Garcia-Misa, Consultant / Production Coordinator for Wipfli Web Marketing.