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SEO and AI
Home / Insights / ＿

How to improve the SEO and AI-friendliness of your PDFs

While HTML remains the top choice for SEO and AI, many organisations still rely on PDFs. This guide offers practical strategies to optimise your PDFs for better discoverability and readability by search engines and AI tools.

Shayna Burns

11 November 2026

7 minute read

Originally posted July 2025, updated November 2026

While HTML content remains the most SEO- and AI-friendly format, many organisations continue to use PDFs due to their convenience, printability, and control over formatting - and because sometimes publishing a PDF is easier than trying to create a page in your CMS. Even Google’s Martin Splitt said PDFs make sense when you need precise print formatting or interactive elements like forms.

If your content must be in PDF format for whatever reason, spending the time to optimise your documents for AI and search engine accessibility becomes critical to ensuring they get found.

Below we cover how marketers and content managers can enhance PDFs to ensure they can be read and found in AI search and answer engines.

New insight in 2026: How Google reads your PDFs

In an October 2026 podcast, Google engineer Martin Slitt explained that Google doesn’t read PDFs as PDFs. Instead, it converts them into HTML and indexes that version, then ranks them much like any other page. That’s why PDFs can appear in regular search results, AI Overviews and AI Mode. 

This means the cleaner your PDFs convert, the better for findability. Below we have updated our PDF optimisation tips to ensure they come back to the same idea: make it easy to turn your document into well-structured text for both search engines and LLMs.

SEO and generative engine optimisation (GEO) tips for PDFs

Whether you're updating existing PDFs or creating new ones from scratch, making them AI-friendly improves discoverability, readability and usefulness. These practical tips help search engines and AI tools better understand and rank your content.

1. Use clear, descriptive metadata

In our SEO audits, the #1 thing our clients miss when it comes to PDF optimisation is adding metadata.

Every PDF has properties that sit behind the content: title, author, subject and keywords. The title is the one that matters most. Google has confirmed it uses the title field, along with the hyperlinked text (anchor text) of links pointing to your PDF, to decide what title appears in search results. 

Write a title that describes the document the way your audience would search for it, and use the subject field for a short summary. You can skip the keywords field as major search engines haven’t used keyword metadata for years.

How to add metadata in Adobe Acrobat

  1. Open the PDF, then go to File > Properties.
  2. Edit the metadata fields.

How to add metadata when you’re exporting a PDF from Microsoft Word

1. In your Word document, go to File > Info.

2. On the right-hand side (or under Properties drop-down), fill out:

  • Title
  • Author
  • Subject

3. Then go to File > Save As.
Choose PDF as the file format.
Before saving, click Options (next to the Save button), and ensure Document properties is checked under ‘Include non-printing information’.

How to add metadata when you’re exporting a PDF from Google Docs

To add properties to your PDF, you will need to use Adobe Acrobat (instructions above) or an online tool like PDFCandy or Copy Checker to edit the metadata once it’s a PDF. (Security tip: Be mindful of uploading sensitive documents to online tools.)

2. Optimise file names

File names matter. Replace generic names like /doc-123.pdf with descriptive, keyword-rich titles, e.g. /patient-heart-health-guide.pdf, using lowercase words separated by hyphens. This helps signal relevance and improves indexing, as well as giving readers confidence that what they’re clicking on meets their needs.

3. Structure content with clear hierarchy

Use headings (H1, H2, H3), bullet points and numbered lists to create a logical flow of information. A clear hierarchy helps search engines and AI understand content relationships — similar to what our content team recommends for content structuring in HTML pages.

Example:

  • H1: Managing your heart health
    • H2: Diet recommendations
    • H2: Exercise guidelines
      • H3: Resistance training
      • H3: Cardiovascular training
    • H2: Stress management techniques

Set your headings using real heading styles (Heading 1, Heading 2, etc. in Word), not just bigger, bolder text. When you export with tagging turned on, those styles become tags in the PDF.

Note: Neither Google nor other search engines have confirmed that they read PDF tags, but tagged PDFs are essential for accessibility. They also keep your reading order intact and assist tools in PDF-to-HTML conversions. 

4. Make content machine-readable

For scanned or image-based PDFs, run Optical Character Recognition (OCR) to convert images into text. This ensures AI can read, interpret and index the document properly.

Running OCR in Adobe Acrobat

Note: this requires Adobe Acrobat Pro.

  1. Open the scanned PDF in Adobe Acrobat Pro.
  2. Go to Tools > Scan & OCR.
  3. Click Recognize Text > In This File.
  4. Choose the correct language.
  5. Click Recognize Text to run OCR.
  6. Save the file. The text is now searchable and selectable.

Running OCR in Google Docs

  1. When opening a scanned PDF or image in Google Docs, Google will automatically run OCR and open the file with recognised text. 
  2. From here, review the output and make edits needed. Then, download it as a PDF.

There are online tools available, too, but these are not appropriate for sensitive documents.

5. Add alt text for images

Add alt tags to all images, diagrams and charts. These tags describe visual content, improving accessibility and helping AI interpret visual elements. If you’re exporting from Word, add alt text to images before you export and it will carry through to your tagged PDF.

Example: ‘Diagram of heart anatomy highlighting atria and ventricles’.

6. Use simple, consistent layouts

Avoid overly complex layouts or multi-column text unless necessary. Linear, easy-to-follow formats help both AI and human readers understand your content more easily.

7. Write in plain, concise language

Use clear and simple language. This improves understanding for diverse readers and helps AI tools summarise or repurpose content accurately. Reference your brand guidelines for any requirements around reading levels.

8. Keep file sizes lean

Every crawler has a limit on how much of a file it will download. For example, Google crawls the first 64MB of a PDF. If the PDF is packed with uncompressed images, content beyond the cutoff may not be indexed. In your PDFs, compress images, put your most important content early in the document, and consider splitting very long reports with images into separate, focused documents. 

9. Keep content updated and relevant

Regularly review and update PDFs to ensure accuracy and timeliness. AI prioritises fresh, relevant content.

10. Link internally and externally

Include internal links to related resources and external links to authoritative sources. Linking improves both user experience and search engine ranking.

11. Build PDF governance into your style guide

Retrospectively updating PDFs can be costly and time consuming, so setting them up correctly in the first place is the best approach. By incorporating PDF governance in your style guide and sharing them across your organisation, you’ll help to ensure they’re written and built optimally.

A simple pre-publish checklist helps:

  • Title metadata filled in
  • Headings set with heading styles and the PDF exporters with tags 
  • Alt text added to images
  • File size checked
  • Not gated, unless that’s a deliberate choice

A real-world example of the importance of optimising PDFs

Doctors frequently offer printable PDFs containing treatment guidelines or condition information to patients. Using simple language and well structured content helps to improve PDF readability.

Patients may also choose to search for information online. By ensuring PDFs are AI-friendly, healthcare providers can help patients discover trustworthy medical resources more easily through search engines and AI search, improving overall patient care and resource visibility.

FAQs on PDFs and AI optimisation

HTML is inherently structured for search engines and AI, providing better accessibility and easier indexing. Try to avoid having your content only in PDF format, and be sure to structure it with <h> tags when you do. Where possible, replicate the content in HTML and give users the option to download a PDF.

Yes, optimising metadata, applying Optimal Character Recognition (OCR) and using descriptive filenames can greatly improve SEO on existing PDFs.

Update PDFs whenever content becomes outdated or when there's new, relevant information available. Search engines and LLMs love fresh content (it gives them something new to share).

Whilst HTML content remains the gold standard for AI-friendliness, implementing these recommendations for your PDFs will ensure they stay relevant, accessible and discoverable in AI-driven search.

Speaking of HTML content, have you reviewed your pages for AI friendliness? See our practical guide to writing Al-friendly copy.

Shayna Burns

11 November 2026

7 minute read

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