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
- Upload one or more PDF files.
- Select a PDF/A Version from the dropdown.
- Optionally enable Pre-flatten PDF for complex files that fail normal conversion.
- Click Convert to PDF/A. Multiple files produce a ZIP archive.
PDF/A Versions
| Version | Restrictions | Best For |
|---|---|---|
| PDF/A-1b | Strictest. No transparency, no layers. | Maximum compatibility with older archival systems |
| PDF/A-2b | Allows transparency and JPEG2000. | General-purpose archiving (recommended) |
| PDF/A-3b | Allows 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.
Related Tools
- Compress PDF -- reduce the file size after conversion
- Flatten PDF -- flatten forms before converting to PDF/A
- Remove Metadata -- strip metadata before archiving