How to Test a PDF for Accessibility – Tools and Techniques

Creating a PDF is easy, but making sure it’s accessible is where the real challenge lies. Many PDFs look fine visually but are difficult or even impossible to navigate with assistive technologies. That’s why a PDF accessibility test is essential.

In this section, we’ll look at simple manual checks anyone can do, along with specialised tools that highlight accessibility issues and suggest fixes. Together, these techniques give you a clear picture of how accessible your PDF really is.

How to Test a PDF for Accessibility

To test a PDF for accessibility, start by checking six essentials: keyboard navigation, reading order, colour reliance, colour contrast, image descriptions, and metadata. These tests will show if your PDF works for everyone.

1. The keyboard navigation test

What you’re testing: Can people move through your PDF using only a keyboard?

Why this matters: Many people with disabilities rely on the keyboard instead of a mouse to read and interact with documents. If your PDF doesn’t support keyboard navigation, you’re putting up unnecessary barriers that prevent them from accessing your content.

What causes this: Keyboard issues usually occur when the PDF isn’t properly tagged or when no tab order is set. Without that structure, the focus can jump around, skip elements, or get stuck, making the document frustrating, or even impossible, to use.

How to Test It	What to Look For	Red Flags
Open your PDF and set the mouse aside. Use only the keyboard: – Tab to move forward through interactive elements – Shift + Tab to move backwards – Enter to activate links or buttons	– You can reach every link, button, and form field. – The tab order flows logically and predictably. – You can move through the document without getting stuck.	– Some elements can’t be reached at all. – Tab order jumps around in a confusing way. – The focus gets trapped in one section.

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2. The reading order test

What you’re testing: Does the screen reader read the PDF in the right order?

Why this matters: A clear reading order is essential for people using screen readers. Otherwise, they will hear content out of sequence, making the document confusing or unusable.

What causes this: Reading order problems usually happen when content is arranged visually but not structurally. Without proper tagging, screen readers follow the order in which elements were added, not how they appear on the page. Images without alt text also leave big gaps in meaning.

How to Test It	What to Look For	Red Flags
In Adobe Acrobat: – Go to View > Read Out Loud > Activate Read Out Loud – Then choose Read This Page Only	– Text flows in a logical order. – Images are announced with clear, meaningful descriptions. – Reading order matches how the content appears on the page.	– Content jumps around or reads out of sequence. – Images are read as “image” or by filename. – Sidebars or footers interrupt the main text.

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3. The colour contrast check

What you’re testing: Does the text have enough contrast with the background to be readable?

Why this matters: Low contrast text is hard to read for everyone, but especially for people with low vision or colour blindness. Even if your content passes the colour reliance (grayscale) check, poor contrast can still make it inaccessible.

What causes this: Designers often choose light text on light backgrounds (like grey on white) or trendy colour combinations that don’t meet accessibility standards.

How to Test It	What to Look For	Red Flags
Use a tool like WebYes Colour Contrast Checker (free)	Text/background combinations meet WCAG 2.1 contrast ratios: – Normal text: 4.5:1 minimum – Large text (18pt+): 3:1 minimum	– Text looks “washed out” or hard to read. – Light grey on white, or low-contrast colour pairs. – Fails WCAG contrast ratio tests.

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4. The colour reliance check

What you’re testing: Does your PDF still make sense without colour?

Why this matters: If your document relies only on colour to communicate meaning, important details can be lost for people with colour blindness or those using grayscale mode. This simple check shows whether your content works even without colour cues.

What causes this: Colour reliance issues happen when visual cues aren’t backed up with text, patterns, or labels. Charts without labels, links styled only by colour, and instructions like “see items in red” are common culprits.

How to Test It	What to Look For	Red Flags
Switch your device to grayscale mode: – Windows: Settings > Ease of Access > Colour filters > Grayscale – Mac: System Preferences > Accessibility > Display > Grayscale – iOS: Settings > Accessibility > Display & Text Size > Colour Filters > Grayscale – Android: Settings > Accessibility > Colour correction > Grayscale	– All information is still clear and understandable. – Links stand out from regular text. – Charts and graphs remain readable and distinct.	– Important information disappears or becomes unclear. – Links blend into the surrounding text. – Chart data becomes hard to interpret.

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5. The image description check

What you’re testing: Do images have meaningful descriptions that add context?

Why this matters: If an image has no alt text or if the description is vague or misleading, screen readers can’t explain the image properly. This leaves people missing important details, especially when the image conveys information not explained elsewhere in the document.

What causes this: Missing or poor alt text happens when images are inserted without descriptions, or when descriptions are too vague (like “image1.jpg”) or redundant (“logo”).

How to Test It	What to Look For	Red Flags
– Hover over images to see if text appears. – In Adobe Acrobat, use Read Out Loud to hear how images are announced.	– Important images have meaningful descriptions. – Decorative images are marked as decorative, so they’re skipped. – Descriptions give context without being repetitive.	– Hovering shows nothing or only a filename. – Images are announced as “image” or with vague text. – Decorative graphics are read aloud unnecessarily.

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6. The metadata check

What you’re testing: Does the PDF have a proper title and the correct language set?

Why this matters: When a PDF opens, screen readers announce the document title first. If it says “Untitled,” users don’t know what file they’re in. Setting the document language ensures screen readers pronounce text correctly.

What causes this: Authors often skip filling in document properties or forget to set the language before exporting the PDF.

How to Test It	What to Look For	Red Flags
In Acrobat: – Go to File > Document properties > Description to check the Title. – Then switch to the Advanced tab to confirm the Language.	– The title field is filled with a clear, meaningful name. – Language is set correctly (e.g., English, French, etc.).	– The title is blank or “Untitled Document.” – Language field not specified.

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Best Tools for Testing PDF Accessibility

So far, we’ve looked at simple ways to test a PDF manually. But there are also tools that can make the job easier. These automated tools catch many common accessibility issues and provide a strong starting point before you move on to deeper manual checks.

1. Adobe Acrobat Pro

Adobe Acrobat Pro is the most widely used professional tool for PDF accessibility testing. Its Prepare for accessibility feature scans your PDF for common issues such as missing tags, incorrect reading order, unlabeled form fields, and missing metadata.

One of Acrobat Pro’s key strengths is that it does more than test. It also helps you fix the issues it finds. Depending on the problem, Acrobat can apply an automatic fix or open a dialog box that guides you through the manual steps needed to correct it.

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2. PAC 2024

PAC 2024 is a Windows-based PDF accessibility testing tool that fully checks whether a PDF is compliant with PDF/UA and meets WCAG 2.1 requirements. In addition, it runs quality tests that are not legally required but help improve usability.

One useful feature is the screen reader preview, which shows what a screen reader will “see” as it reads the page. The tool also provides detailed reports that highlight structural issues and make it easier to understand where accessibility improvements are needed.

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3. MAUVE++

Mauve is a web-based tool for checking PDF accessibility. You can upload a file or enter a URL, and it tests your PDF against four WCAG 2.1 requirements (PDF 3, PDF 9, PDF 13, and PDF 18). It also runs three Mauve best-practice checks.

The advantage of Mauve is that you can run quick accessibility tests right in your browser with no installation or subscription required. The downside is that it only covers a limited set of checks, so it cannot be relied on for full WCAG compliance testing.

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PDF Accessibility Best Practices

It’s always easier to build accessibility in from the start than to fix problems later. When you create PDFs with accessibility in mind, you save time, avoid costly fixes later, and ensure your content is usable by everyone right from the start.

Here are some best practices to follow:

1. Ask if it really needs to be a PDF: A PDF is not always the most accessible option. Think about your audience and the content type before defaulting to this format.
   • If your PDF is a form: Consider using a web form (such as Google Forms or Qualtrics). These are easier to fill out, update, and make accessible.
   • If your PDF is informational: Publishing the content as a web page is often better. HTML is generally more accessible, easier to maintain, and more mobile-friendly.
2. Start with an accessible source document: Whether you’re working in Word, Google Docs, or InDesign, add accessibility to your source file before converting to PDF. Use heading styles, alt text, and proper table formatting so these elements carry over when you export.
3. Keep accessibility settings when exporting: Always export to PDF with accessibility settings enabled. Use the “Save as PDF” or “Export as PDF” functions, not “Print to PDF,” which strips out tags and accessibility features.
4. Test before sharing: Run the accessibility checks covered in this guide and, where possible, preview your PDF with a screen reader. Automated tools are helpful, but manual testing ensures your content is truly usable.

Wrapping Up

Accessible PDFs make your content easier to use and understand for everyone, regardless of their abilities. The techniques and tools discussed in this guide help you remove common barriers and ensure your documents work as intended.

With the European Accessibility Act (EAA) now in effect, PDF accessibility is mandatory (for those under the scope). By building accessibility in from the start and testing your PDFs before publishing, you can meet legal requirements and create inclusive content.