PDF Accessibility Tools Compared: What Works in 2026
Over 97% of PDFs on the web fail basic accessibility checks. With ADA Title II digital deadlines in 2026 and EU accessibility laws taking effect, picking the right tool matters more than ever.
Why PDF Accessibility Tools Exist
Most PDFs are created without structure tags, alt text, or reading order — the building blocks screen readers need. A sighted person opens a PDF and sees a nicely formatted document. A blind person using JAWS or NVDA hears a jumbled mess, or nothing at all.
Regulations are catching up. ADA Title II now requires state and local governments to make web content accessible by April 2026. The European Accessibility Act (EAA) applies to private-sector digital products starting June 2025. Fines under ADA settlements regularly exceed $75,000.
Manual PDF remediation — adding tags, alt text, reading order, and table headers by hand — takes 2 to 4 hours per document. Automated tools cut that to minutes for simple files, though complex layouts still need human review.
Quick Comparison: 6 PDF Accessibility Tools
Annual pricing, platform, and key capabilities at a glance.
| Tool | Price (annual) | Platform | Auto-tagging | Standards | AI features | API access | Free tier |
|---|---|---|---|---|---|---|---|
| Adobe Acrobat Pro | $239.88/yr | Desktop + Cloud | Yes | WCAG 2.0, Section 508, PDF/UA | Limited | No | 7-day trial |
| CommonLook PDF | ~$3,000/yr | Desktop (Windows) | Yes | WCAG 2.1, Section 508, PDF/UA, HHS | No | No | No |
| Equidox | Custom quote | Cloud | Yes | WCAG 2.1, Section 508, PDF/UA | Yes (zone detection) | Yes | Demo only |
| PAVE | Free | Browser | Partial | PDF/UA | No | No | Yes (full) |
| PREP (Continual Engine) | Custom quote | Cloud | Yes | WCAG 2.1, Section 508, PDF/UA | Yes (AI-first) | Yes | No |
| PDFlys | Free / Pro plans | Browser | No | WCAG 2.1, Section 508, PDF/UA, EN 301 549 | Yes (suggestions) | Yes | Yes (no time limit) |
Tool-by-Tool Breakdown
What each tool does well, where it falls short, and who it fits best.
Adobe Acrobat Pro
The industry standard for PDF creation and editing. Acrobat Pro includes a built-in accessibility checker and a tag editor for manual remediation. Most accessibility professionals know the Acrobat workflow, which makes hiring and training easier. The checker covers WCAG 2.0 criteria and can auto-tag simple documents.
Strengths
Full tag editor for manual remediation. Broad industry familiarity. Integrated into Creative Cloud. Handles complex layouts with manual effort.
Limitations
Expensive for accessibility-only use ($239.88/yr). Auto-tagging misses complex tables and forms. Checker still references WCAG 2.0, not 2.1. No API for batch processing. Learning curve for the tag tree editor.
Best for
Organizations already paying for Creative Cloud that need both PDF editing and accessibility checking in one tool.
CommonLook PDF
A Windows desktop application built specifically for PDF accessibility remediation. CommonLook is used heavily in government and higher education, where full PDF/UA conformance is required. It provides a structured tag editor with visual mapping between tags and page content. It also supports HHS-specific requirements for health-related documents.
Strengths
Purpose-built for remediation. Visual tag-to-content mapping. Handles complex tables and nested lists well. HHS standards support. Strong in government and education sectors.
Limitations
Windows only — no Mac or Linux support. High cost (~$3,000/yr per seat). Steep learning curve. No cloud or browser option. No free tier or trial.
Best for
Government agencies and universities that need full PDF/UA conformance and have trained accessibility specialists on staff.
Equidox
A cloud-based remediation platform that uses zone-based detection to speed up tagging. Equidox identifies page regions (headings, paragraphs, images, tables) and lets operators confirm or adjust the suggested tags. It targets organizations processing moderate to high volumes of documents.
Strengths
Cloud-based — no install. Zone detection reduces manual work. Good table remediation tools. API for integration. Collaboration features for teams.
Limitations
Custom pricing (no public rates). Requires uploading files to their servers. Still needs human review for accuracy. Not suited for one-off documents.
Best for
Compliance teams at universities, publishers, and government contractors processing 50+ documents per month.
PAVE (PDF Accessibility Validation Engine)
A free, browser-based tool from the Zurich University of Applied Sciences. PAVE checks PDFs against PDF/UA and provides a guided remediation workflow. It is one of the few fully free options for PDF accessibility work. The tool focuses on PDF/UA rather than WCAG, which limits its scope for web accessibility compliance.
Strengths
Completely free with no usage limits. Browser-based — works on any platform. Guided remediation workflow. Academic backing from ZHAW.
Limitations
Covers PDF/UA only — no WCAG 2.1 or Section 508 checking. Limited auto-remediation. Requires file upload. No API. Slower on large documents.
Best for
Students, solo creators, and small organizations that need basic PDF/UA checking without a budget.
PREP (Continual Engine)
An AI-driven remediation platform that automates most of the tagging process. PREP uses machine learning to detect document structure and apply tags at scale. It is designed for organizations with large document backlogs — thousands of PDFs that need remediation. Continual Engine markets PREP as achieving 80–95% automation rates.
Strengths
High automation rate for bulk processing. AI-driven structure detection. Handles large backlogs. VPAT generation. API access for pipeline integration.
Limitations
Custom pricing only — no public rates. Claims of 80–95% automation are hard to verify independently. Requires file upload to their cloud. Less suited for one-off documents. Smaller user community than Acrobat.
Best for
Enterprises and large institutions with thousands of legacy PDFs to remediate under a compliance deadline.
PDFlys
A browser-based PDF toolkit with a built-in accessibility checker. PDFlys runs 39 checks across WCAG 2.1, Section 508, PDF/UA, and EN 301 549. It identifies issues, scores the document, and offers 7 instant fixes (like adding language declarations and display titles). AI-powered suggestions help with alt text and heading structure. Files stay in the browser — nothing is uploaded for checking.
Strengths
39 checks across 4 standards. No file upload — runs in the browser. 7 instant auto-fixes. AI suggestions for alt text and structure. Shareable audit reports. MCP server for AI agent integration. Free tier with no time limit. 30+ other PDF tools in the same app.
Limitations
No manual tag editor for full remediation. Automated checks cover about 30–40% of WCAG criteria (manual review still needed for the rest). No batch processing yet. AI fixes require the server-side API. Newer tool — smaller user community than Acrobat or CommonLook.
Best for
Web developers, content creators, and small compliance teams that need fast accessibility checks and basic fixes without installing software or paying upfront.
Feature-by-Feature Comparison
Detailed breakdown across five categories: standards, detection, remediation, reporting, and integration.
Standards Coverage
| Feature | Adobe | CommonLook | Equidox | PAVE | PREP | PDFlys |
|---|---|---|---|---|---|---|
| WCAG 2.1 Level AA | Partial (2.0) | Yes | Yes | No | Yes | Yes |
| WCAG 2.2 | No | Partial | Partial | No | Partial | No |
| Section 508 | Yes | Yes | Yes | No | Yes | Yes |
| PDF/UA-1 | Yes | Yes | Yes | Yes | Yes | Yes |
| EN 301 549 | No | Partial | No | No | No | Yes |
| HHS Standards | No | Yes | No | No | No | No |
Detection Capabilities
| Feature | Adobe | CommonLook | Equidox | PAVE | PREP | PDFlys |
|---|---|---|---|---|---|---|
| Document structure tags | Yes | Yes | Yes | Yes | Yes | Yes |
| Image alt text | Yes | Yes | Yes | Yes | Yes | Yes |
| Table structure | Partial | Yes | Yes | Partial | Yes | Yes |
| Reading order | Yes | Yes | Yes | Yes | Yes | Yes |
| Color contrast | No | No | No | No | Partial | Yes |
| Form field labels | Yes | Yes | Yes | Partial | Yes | Yes |
| Heading hierarchy | Partial | Yes | Yes | Partial | Yes | Yes |
| Bookmark structure | Yes | Yes | Partial | No | Partial | Yes |
Remediation
| Feature | Adobe | CommonLook | Equidox | PAVE | PREP | PDFlys |
|---|---|---|---|---|---|---|
| Manual tag editor | Yes | Yes | Partial | Partial | No | No |
| Auto-tagging | Yes | Yes | Yes | Partial | Yes | No |
| AI-powered suggestions | Limited | No | Yes | No | Yes | Yes |
| Instant auto-fixes | Partial | No | No | No | Yes | Yes (7 fixes) |
| Alt text generation | No | No | No | No | Yes | Yes (AI) |
| Batch processing | Yes (Action Wizard) | Yes | Yes | No | Yes | No |
Reporting
| Feature | Adobe | CommonLook | Equidox | PAVE | PREP | PDFlys |
|---|---|---|---|---|---|---|
| PDF audit report | Yes | Yes | Yes | Yes | Yes | Yes |
| CSV/Excel export | No | Yes | Yes | No | Yes | Yes |
| Shareable report link | No | No | Yes | No | No | Yes |
| Compliance evidence | Partial | Yes | Yes | No | Yes | Yes (hashed) |
| VPAT generation | No | No | No | No | Yes | No |
Integration
| Feature | Adobe | CommonLook | Equidox | PAVE | PREP | PDFlys |
|---|---|---|---|---|---|---|
| REST API | No | No | Yes | No | Yes | Yes |
| MCP server | No | No | No | No | No | Yes |
| CI/CD integration | No | No | Partial | No | Yes | Yes |
| LMS integration | No | Partial | Yes | No | Yes | No |
| Browser-based (no install) | Partial (web app) | No | Yes | Yes | Yes | Yes |
What Sets PDFlys Apart
No file upload for checking
The accessibility checker runs entirely in your browser. Your PDF never leaves your device during the audit — no server round-trip, no data retention concerns.
Free tier with no time limit
Run accessibility checks and get audit reports without creating an account or entering a credit card. The free tier has no expiration date.
30+ PDF tools in one app
Beyond accessibility, PDFlys handles merging, splitting, compressing, editing, signing, redacting, watermarking, and converting PDFs — all from the same interface.
MCP server for AI agents
Connect Claude, GPT, Cursor, or any MCP-compatible AI assistant to PDFlys. Run accessibility checks, apply fixes, and generate reports through natural language.
Shareable audit reports
Generate a report link you can send to colleagues, clients, or auditors. Reports include evidence hashing for integrity verification.
8-language interface
The full application — including accessibility checker, reports, and all PDF tools — is available in English, Spanish, French, German, Portuguese, Hindi, Arabic, and Indonesian.
What PDFlys Doesn't Do (Yet)
No tool covers everything. Here is where PDFlys falls short compared to specialized remediation software.
No manual tag editor
CommonLook and Adobe Acrobat let you edit the PDF tag tree directly — moving, renaming, and restructuring tags. PDFlys does not have a tag editor. For documents that need full manual remediation, you will still need desktop software.
Partial criterion coverage
PDFlys checks 39 criteria across 4 standards, which covers roughly 30–40% of all WCAG 2.1 success criteria. The remaining criteria require manual testing (keyboard navigation, cognitive load, content meaning) that no automated tool can fully cover.
No batch processing
You can check one document at a time. If you have hundreds or thousands of PDFs to remediate, tools like PREP, Equidox, or Acrobat's Action Wizard are better suited for bulk work.
AI fixes need the API
The 7 instant fixes run locally, but AI-powered suggestions (alt text generation, heading structure) require the server-side API. This means those features need an internet connection and are subject to API usage limits.
Which Tool Fits Your Situation?
Solo creator or small business
PDFlys or PAVE
- Budget is tight or nonexistent — both have free tiers
- Document volume is low (under 10 PDFs per month)
- You need a quick check before publishing, not full remediation
- PDFlys covers more standards (WCAG 2.1, Section 508, EN 301 549) while PAVE focuses on PDF/UA
Compliance team at a university or agency
PDFlys, Equidox, or CommonLook
- You need WCAG 2.1 and Section 508 coverage for regulatory compliance
- Document volume is moderate (10–100 per month)
- PDFlys works for initial checks and quick fixes at no cost
- Equidox or CommonLook is better when documents need full manual remediation
Enterprise with 10,000+ document backlog
PREP or CommonLook
- You need batch processing and high automation rates
- Budget allows for enterprise licensing
- Integration with existing document workflows matters
- PREP handles bulk AI-driven remediation; CommonLook handles complex manual work
Developer building an accessible PDF pipeline
PDFlys API + MCP
- You need API access to run accessibility checks programmatically
- MCP integration lets AI agents check and fix PDFs in automated workflows
- CI/CD integration catches accessibility regressions before deployment
- Free tier covers development and testing; paid plans for production volume
Frequently Asked Questions
What is PDF remediation?
Which PDF accessibility standard do I need to follow?
Can AI fully fix an inaccessible PDF?
Is PAVE really free?
How does PDFlys compare to Adobe Acrobat for accessibility?
What is the difference between WCAG and PDF/UA?
Do I need Section 508 compliance?
Can I check accessibility without uploading my file?
What does a PDF accessibility audit include?
How long does manual PDF remediation take?
What are the penalties for inaccessible PDFs?
Does PDFlys work with scanned PDFs?
Check Your PDF's Accessibility — Free
Drop a PDF into the checker and get a scored audit report in under 30 seconds. No signup, no upload, no cost. See exactly what passes, what fails, and how to fix it.