Ashish Tiwari

What Is A PDF Accessibility Checker? What Does It Do?

A PDF accessibility checker is a digital tool that checks whether a PDF document is accessible (readable) to everyone, including people with visual disabilities. CommonLook PDF Validator and PAC3 are two powerful PDF accessibility checkers that check the accessibility of PDF documents.  

The Portable Document Format, abbreviated as PDF, is the native file format of the Adobe Acrobat family of products. The format allows users to view and share electronic documents conveniently and without the loss of any information. This is important because the loss of even the smallest bit of information can potentially tamper the overall accuracy and value of the document in question.

Thanks to the power of this format, most government and private organizations all over the world publish PDF documents on their websites, apps and other digital offerings which are then accessed by the general public.

But here’s the problem: most PDF documents published online are not truly accessible. In other words, they may not be read (in the way they were intended) by everyone, including people with disabilities.

This is where PDF accessibility comes into the picture.

What is PDF accessibility?

A PDF document is considered accessible if it can be read by everyone, including people with disabilities; this includes access by people who are blind, visually impaired, cognitively impaired or color-blind. An accessible PDF makes it easier for people with disabilities to access PDF documents with the aid of assistive technology software and devices, like screen magnifiers, screen readers, speech-recognition software, text-to-speech software, alternative input devices and refreshable Braille displays.

You can read about accessible PDFs in detail here: What’s an accessible PDF and what does it look like?

The term PDF accessibility generally refers to the attribute of a PDF document being accessible to all users, including people with disabilities.

Most PDF documents published on the web are not created with PDF accessibility in mind, which is why organizations get sued for publishing inaccessible documents on their digital assets.

If you create a PDF document and want to ensure that it is accessible, what do you do? And how do you check a PDF for accessibility?

You use a PDF accessibility checker.

What is a PDF accessibility checker?

Simply put, it’s a software that tests whether a given PDF document is accessible or not. In order to do that, most accessibility checkers run the PDF document through a set of predetermined tests and checkpoints. If the document passes those tests, then it’s deemed as an accessible PDF.

There are only a few PDF accessibility checkers available on the web, here is how to choose the best one for your organization.

Features of an effective PDF accessibility checker

  • It tests against certain compliance standards, including WCAG 2.0, WCAG 2.1, PDF/UA and HHS standards. These are names of well-known standards that help determine whether a PDF is accessible. A good PDF accessibility checker should be able to test your PDF documents against these standards. You don’t want to be in a situation where a PDF accessibility checker tells you that your document is accessible, but when you publish it on your website, you get feedback from users that it’s not really accessible after all. To make matters even worse, you can get sued for publishing inaccessible PDF documents on your website which might be used by hundreds, thousands or even millions of users.
  • It should provide a compliance report of accessibility. A certification report provides a breakdown of the accessibility status of your PDF document according to the chosen accessibility standard.
  • It should be free. You may not want to pay to use a software tool just to verify your PDFs . If you can get a free PDF accessibility checker that you can trust, what could be better!

As mentioned earlier, there are a few PDF accessibility checkers available on the web, but given below are two most popular software tools for checking PDF accessibility.

2 Powerful PDF Accessibility Checkers

(1) CommonLook PDF Validator

CommonLook PDF Validator is a FREE plugin for Adobe Acrobat Pro or DC that tests and verifies PDF documents.

What sets CommonLook PDF Validator apart from any other tool of this kind is that tests against Section 508, WCAG 2.0 AA, PDF/UA and HHS standards. Unlike other PDF verification products, CommonLook PDF Validator provides a compliance report for each tested document.

Communications and compliance specialists can rest assured that their PDFs are compliant with accessibility standards. With other verification products, documents can sometimes pass the tests, but still not be accessible and compliant. With CommonLook PDF Validator, you don’t ever have to worry about that problem.

Download PDF Validator for free 

(2) PAC3

The PDF Accessibility Checker (PAC) 3 is freeware from the Swiss foundation “Access for all” for PDF accessibility testing. The freeware program PAC provides a fast way to test the accessibility of PDF files. The tool provides a PDF/UA-check with all machine-testable checkpoints of the Matterhorn protocol.

A disadvantage of PAC3 is that it doesn’t test for conformance against all established accessibility standards. Only CommonLook PDF Validator tests against not only PDF/UA but also WCAG 2.0 (A and AA), the HHS 2018 standard, the “original” Section 508, and the “original” HHS standard as well (both Section 508 and the HHS standard have been updated within the past couple of years).