A11ysaurio PDF Checker vs AlphaPrepress PDF Preflight: Which Should You Choose?

Who this comparison is for

If you searched for a "PDF checker plugin for WordPress" and landed on both of these, it's worth clearing something up immediately: A11ysaurio PDF Checker and AlphaPrepress PDF Preflight both check PDFs, both run on your own server/browser rather than a third-party API, and both are free WordPress.org repository plugins — but they check for almost entirely different things. One is about accessibility compliance. The other is about print-production readiness. This comparison is for anyone trying to figure out which of these two overlaps with their actual problem, not for anyone deciding between them as interchangeable options.

Pricing

There's effectively no pricing decision to make between these two — both are free right now. A11ysaurio is explicitly and permanently free: it's open-source GPL software with a single tier, no premium upsell, no account, and no per-scan fees, since all analysis happens client-side in the browser with no backend doing the work. AlphaPrepress PDF Preflight is also free to install via the WordPress.org repository today, but its pricing situation is less settled — there's no published pricing page, no premium tier yet, and the guide notes this could simply be a pre-monetization phase before a paid "Pro" tier arrives, meaning advanced checks or higher-volume processing could get gated later. If you need pricing certainty going forward, A11ysaurio's zero-dollar model is a firmer commitment than AlphaPrepress's current free-for-now state.

Features and processing model

Both plugins share a privacy-conscious architecture: neither ships your PDFs to an external scanning service. A11ysaurio does its analysis entirely client-side in the browser using JavaScript, so files never leave your machine. AlphaPrepress parses PDF structure natively on your own server, so files stay within your hosting environment. That's where the similarity ends.

A11ysaurio checks for accessibility and compliance issues: document tagging, image alt text, reading order, language declaration, heading structure, and scanned/image-only detection, mapped to WCAG 2.1 and PDF/UA (ISO 14289) requirements. It surfaces results as a report attached to the file right in the Media Library.

AlphaPrepress checks for print-production readiness: valid PDF structure, embedded/missing fonts, image resolution (DPI), color space (RGB vs CMYK vs spot), and bleed/trim box presence. It generates a quality score and is built to hook into WooCommerce upload flows — for example, scoring customer-submitted artwork before it reaches a prepress team. Neither plugin fixes the problems it finds; both are flagging tools, not correction engines.

Comparison table

	A11ysaurio PDF Checker	AlphaPrepress PDF Preflight
Price	Free, single tier, open source (GPL)	Free via WordPress.org repo currently; no published pricing, possible future paid tier
Best for	Sites publishing PDFs (syllabi, reports, minutes, spec sheets) that need WCAG/PDF-UA compliance checks	WooCommerce print shops, promo/apparel stores, or brand asset portals needing print-readiness checks
Standout feature	Fully client-side (browser) analysis — PDFs never leave your machine	WooCommerce upload-step integration with an automated quality score
What it checks	Tagging, alt text, reading order, language, heading structure, scanned/image-only detection	PDF structure validity, font embedding, image DPI, color space, bleed/trim boxes
Maturity	Newly listed, small install base, no meaningful review history	No stated install/review history in current materials; positioned as an early-stage free tool
Support	Community support via WordPress.org forum, no SLA	Support/updates likely community/best-effort, no paid SLA mentioned

Which one should you choose

These two rarely compete for the same buyer, so the choice mostly makes itself once you know your actual problem. If you publish PDFs for the public — course materials, board minutes, grant reports, job listings — and need to know whether they're readable by screen readers or meet WCAG/PDF-UA standards, A11ysaurio PDF Checker is the relevant tool, and it costs nothing to try since it's a fixed free product with no roadmap uncertainty. If you run a WooCommerce store where customers upload their own artwork for printing — business cards, signage, apparel, packaging — and you want to catch low-resolution logos, wrong color spaces, or missing bleed before a job goes to print, AlphaPrepress PDF Preflight is the fit, with the caveat that its long-term pricing model isn't locked in yet, so don't assume today's free access is permanent. A site that does both public PDF publishing and print-on-demand commerce could reasonably run both, since neither charges for the privilege and neither would step on the other's checks.