Research program

What survives document conversion, measured in public.

Seven studies on the questions nobody benchmarks: whether headings, tables, reading order, links, and equations keep their meaning when PDFs become HTML, and what real-world tagging does to assistive technology along the way.

Registered evidence only

Every number we publish traces to recorded evidence with a stated method and version. Findings that have not been measured are labeled planned, never implied.

Our pipeline plays by the same rules

Our own conversion pipeline is scored with the same frozen methods as everything else we measure, and its failures are published with the same detail as its wins.

Reproducible by design

Corpora are acquired from official public URLs with recorded hashes and malware scans. Methods are versioned. When a method changes, the change is disclosed.

Research briefs

7 studies. Statuses are factual, not aspirational.

  1. 01 · Flagship benchmark

    Collecting evidence

    The Accessible HTML Conversion Benchmark

    A public benchmark for what no document parser is measured on today: whether a converted document's headings, tables, reading order, links, and alternatives are faithful and usable with assistive technology.

    • Benchmarks
    • WCAG
    • Document conversion
  2. 02 · Field study

    Collecting evidence

    Broken Tags in the Wild: PDF Tagging Pathologies

    A prevalence study of the tagging mistakes that make technically tagged PDFs unusable in practice, measured across public government documents.

    • PDF/UA
    • Tagged PDF
    • Field data
  3. 03 · Recurring index

    Planned

    The ADA Title II Document Readiness Index

    A recurring, sector-stratified measurement of how ready state and local government documents are for the April 2027 and April 2028 web accessibility deadlines.

    • ADA Title II
    • Public sector
    • Compliance
  4. 04 · Measurement study

    Collecting evidence

    Do Links Survive? Link Integrity Through PDF Conversion

    The first measurement of whether hyperlinks keep their text and their destinations when PDFs become HTML, across the three link classes that behave completely differently.

    • Links
    • WCAG 2.4.4
    • Document conversion
  5. 05 · Data study

    Collecting evidence

    The Page Furniture Census

    How much of a government PDF is repeated running headers, footers, and page numbers, and what that repetition costs a screen reader user in listening time.

    • Reading experience
    • Screen readers
    • Field data
  6. 06 · Replication and extension

    Planned

    When Validators Disagree: PDF/UA Checking in Practice

    A checkpoint-level measurement of where PDF/UA validators diverge on the same real files, extending published research that found disagreement on half of documents tested.

    • PDF/UA
    • Validators
    • Standards
  7. 07 · Measurement study

    Planned

    Equations After Conversion: Math in the MathML Core Era

    Every major browser now renders MathML natively, yet equations remain the content most likely to vanish in PDF conversion. This study measures the gap.

    • MathML
    • STEM accessibility
    • Document conversion