ContextQMD
Back to Bentopdf

PDF to PDF/A

docs/tools/pdf-to-pdfa.md

2.7.02.4 KB
Original Source

PDF to PDF/A

PDF/A is an ISO-standardized subset of PDF designed for long-term digital preservation. This tool converts your standard PDFs into PDF/A-compliant documents using Ghostscript running directly in your browser.

How It Works

  1. Upload one or more PDF files.
  2. Select a PDF/A Version from the dropdown.
  3. Optionally enable Pre-flatten PDF for complex files that fail normal conversion.
  4. Click Convert to PDF/A. Multiple files produce a ZIP archive.

PDF/A Versions

VersionRestrictionsBest For
PDF/A-1bStrictest. No transparency, no layers.Maximum compatibility with older archival systems
PDF/A-2bAllows transparency and JPEG2000.General-purpose archiving (recommended)
PDF/A-3bAllows embedded attachments of any format.Archiving documents with source data files

PDF/A-2b is selected by default and works for the vast majority of archiving needs.

Pre-flatten Option

Some PDFs contain features that prevent clean PDF/A conversion -- unusual font encodings, complex transparency stacks, or broken internal structures. Enabling Pre-flatten rasterizes the PDF at 300 DPI before conversion, which guarantees compliance at the cost of making text non-selectable. Use it as a fallback when the standard conversion produces errors.

Pre-flattening requires the PyMuPDF WASM engine.

Use Cases

  • Meeting government or legal archival requirements (many jurisdictions mandate PDF/A for court filings)
  • Submitting documents to institutional repositories or digital libraries
  • Preserving business records where the original software may not exist in ten years
  • Preparing invoices for e-invoicing standards that require PDF/A-3b with XML attachments

Tips

  • Try conversion without pre-flatten first. Only enable it if you get an error.
  • PDF/A embeds all fonts, so output files are often larger than the originals.
  • Validate the output in a dedicated PDF/A validator if strict compliance is required for your workflow.