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The ASPIRE Guide to Accessible PDFs

Part 2: Creating (or improving) PDFs

Alistair McNaught

7 May 2021

An icon of a PDF symbol.
An icon of the thumbs up sign.

Users are addicted to PDFs, but they are the sugary junk food of online content. High on style, low on accessibility. From a user perspective, the basics of an accessible PDF should mean you can:

  • magnify and reflow without weird things happening (like text disappearing at page breaks or gaps between the words disappearing),

  • change the background colour,

  • navigate effectively between headings and subheadings using the bookmark pane,

  • read out loud in a sensible reading order that doesn’t insert page footers and headers in the middle of a paragraph,


In addition, you expect images to be either described or marked as decorative, and hyperlinks to be unique and meaningful on their own (i.e., not “Click here” or “More information” - neither of which mean much anything out of context on a list of page links).

This is a quick two-part guide to how normal people (not specialists!) can ensure their PDFs are accessible to as many users as possible. Part 1 is on creating a PDF from an accessible Word document. Part 2 is about transforming a semi-accessible existing PDF into a more accessible version. In this article we only consider tools that are available to ordinary content creators. Specialists, for example in the marketing department, who use Adobe Acrobat Pro or Adobe InDesign have more options, but these are a tiny minority of staff in a typical public sector body.

1. From Accessible Word to Accessible PDF

An icon of the Word document logo.
A left to right arrow connecting the Word document to the PDF and representing conversion to PDF.
An icon of the PDF logo.


The simplest way to get an accessible PDF is, in theory, to start with an accessible Word document. This works well if the document is simply text with no images.

  1.  Run the accessibility checker on your Word document and fix any issues (Review > Check Accessibility).

  2.  Click file > Export > Create PDF/XPS then in the dialogue box click Options and ensure the following checkboxes are selected:

  • Create bookmarks using Headings.

  • Document structure tags for accessibility.

  • PDF/A compliant.

How good is it?

It’s pretty good, but not perfect. The heading structures will be converted into bookmarks in the Bookmark pane and image descriptions should carry across. However, any pages containing images won’t reflow when magnified using the Zoom > Reflow option in Adobe Reader. That’s a problem.

An icon of the Word document logo.
A cloud download icon, representing using the Adobe cloud to convert to PDF.
An icon of the PDF logo.


This is a quick and easy way and actually works a little better if you have pre-existing accessible Word documents and want to turn them into accessible PDFs.

  1.  Open a browser and enter into the search bar.

  2.  Click on the Select a file button and browse to the Word document on your local device.

  3.  After a few moments (or minutes, depending on the complexity of the document) a message will appear on the page saying Your PDF is ready. You may need to create a free Adobe account in order to download it.

How good is it?

It has all the benefits of the Word export option, but it doesn’t have the issue with images stopping pages reflowing. Although it takes an extra step (uploading to the Adobe webpage) it is the best option for PDFs that include images.

2. From partly accessible Word/PDF to accessible PDF

An icon of a person throwing a document into a trash can, representing the Garbage in, Garbage out principle.

The key thing to remember with any attempt to remediate and improve a document using automatic tools is the GIGO (Garbage In, Garbage Out) principle. No current technology is good at guessing the following:

  • which of the formats you used are for aesthetic effect rather than being structural navigational elements (like a heading or subheading),

  • whether – in your head – bold text was a more important heading than italic or larger font size,

  • the reason and purpose behind an image you added,

  • the most apt description for a hyperlink that currently says “click here”.


Consequently, neither Blackboard nor SensusAccess nor any other conversion tool is going to make a good job of taking your partly accessible documents and making them properly accessible. They may improve some elements based on machine guesswork, but humans are still needed to make something genuinely accessible. The table below shows that a semi accessible Word document cannot be automatically turned into a more accessible PDF by comparing a semi accessible Word document with a tagged PDF created by Blackboard Ally or Sensus Access.

Table 1: Comparing a semi-accessible Word document with the Blackboard Ally or Sensus Access tagged PDF version. 


This depends on the scale at which you’re working.

An icon of 1 large apple and 1 small apple. An arrow points to the small apple. The icon represents working at small-scale.


If you have a manageable number of documents you want to improve and your Word or PDF documents have been created using consistent formatting, it is quick and easy to turn the formatting into appropriate heading styles. Here’s how.

1. Open the document in Word. Word can open most PDF documents as well, giving you an easy way to edit and improve their accessibility.

2. Select the main heading on the page and click Heading 1 on the Styles part of the ribbon.

3. Select one of the 2nd level headings on the page. On the Home tab, under the Editing section, click the Select drop down and choose Select all text with similar formatting.

4. Click Heading 2 on the Styles part of the ribbon.

5. Repeat for 3rd and 4th level headings et cetera. By now, when you open the Navigation pane (View > Navigation pane), you should see the headings listed together.

Next, check none of your hyperlinks have meaningless generic text like “here” or “more”. Then use the Accessibility checker to check for other accessibility issues like image descriptions. Manually check hyperlink text to ensure it is unique and meaningful.

Once you have an accessible Word document, don’t automatically create a PDF to replace it but offer users the option of either Word or PDF. The Immersive Reader (View > Immersive Reader) on Microsoft Word offers significant benefits for many disabled users.

An iocon of a crane, representing working at large scale.


This is much more challenging. Your main options involve using third-party services or licensing a tool from a supplier. The three main options are:


1. Large-scale automated auditing tools: these will allow you to search hundreds or thousands of PDFs and triage the types of issues that exist. They will not pick out every issue (due to the reasons identified above) but they can help you identify if pages have bookmarks or other structural tagging or images have descriptions. They can also pick out the worst content which is merely an image of text. These services help you prioritise.


2. Remediation support tools may be separate to the above or combined with them. They allow you not only to identify the problems in a suite of PDFs but to fix them in a relatively intuitive way. codemantra’s accessibilityInsight platform will validate existing PDFs against PDF/UA standards, attempt to structure your document from existing headings then map all content or design elements (illustrations, pull-out quotes, footnotes, sidebars etc) in an easy to edit format that organises the page’s contents hierarchically. A human operator can rapidly verify the heading hierarchy and reading sequence, rearranging elements for optimal comprehension. The automated validation process also generates a list of all items that require alt text, which can be added into the document via the platform.

PDF with multiple elements and twin column layout . Each element has been tagged by accessibilityInsight using artificial intelligence and the current reading sequence is numbered . It is easy for a content creator to change the headings or the reading order to maximise accessibility.

Figure 1. A screenshot of the accessibilityInsight output showing AI generated hierarchy and reading order.

3. Outsourced remediation: there are two options here:

  • Employ a 3rd party service to do the remediation for you so you end up with accessible PDFs. This would involve a mixture of automated improvements and human mediated improvements using skilled operatives who do this work full-time.

  • Ditch PDFs entirely and get your 3rd party supplier to create HTML or EPUB versions instead.

An icon of a person climbing a mountain, representing the PDF problem.

Your PDF problem will not go away and the longer it takes to start tackling it, the bigger the mountain you’ll have to climb. So here are some recommendations to start climbing the mountain.

  • Make sure EVERYONE who uses PDFs knows how to improve their accessibility – even at a basic level.

  • Where your 3rd party PDFs - from journals or ebooks - have poor accessibility do two things:


1. ​Contact the supplier and ask them about:

(a) alternative more accessible formats (they may have a more accessible online option).

(b) their roadmap is for improvement. If they haven’t got one (or it’s an unrealistically long time frame) look for an alternative.


2. Make sure you signal to the user the level of accessibility they can expect. This might be in an accessibility statement or it might be based on appropriate icons for fully/partially/non accessible.

Unfortunately, if you are a public sector body, the buck stops at you, not the supplier, since you are the body choosing to use inaccessible content for your end users. In many cases it’s unfair, but no more unfair than the barriers disabled people experience online everyday.


Alistair McNaught is one of the architects of the ASPIRE service and a long-term accessibility advocate. Learn more about the services of Alistair McNaught Consultancy. Follow Alistair on Twitter: @alistairm


If you would like to commission an ASPIREreview or have any questions or need help in creating your accessibility statement and telling your story, please contact us at

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