PDF/A is an ISO-standardized version of PDF designed specifically for long-term digital preservation of documents. If someone has asked you to submit a file "in PDF/A format" — whether a court, a government agency, or an archive — this guide explains what that means and why it matters.
The problem PDF/A solves
A regular PDF can depend on external resources — fonts installed on your computer, linked images, embedded JavaScript, multimedia content, or encryption. Open that PDF on a different computer 10 years from now, and it might not render correctly. Fonts might be missing, links might be broken, and interactive elements might not work.
PDF/A eliminates these dependencies. Every resource the document needs — fonts, color profiles, images — must be embedded directly in the file. Features that could break over time (JavaScript, audio/video, external links, encryption) are prohibited. The result is a document that will look exactly the same whether you open it today or in 50 years, on any compliant viewer.
Who requires PDF/A?
- Courts and legal systems — many jurisdictions require electronic court filings in PDF/A format. In the EU, e-filing systems commonly mandate PDF/A.
- Government agencies — tax authorities, regulatory bodies, and public administrations often require PDF/A for official submissions.
- Archives and libraries — national archives, universities, and digital preservation initiatives use PDF/A as their standard format.
- Regulated industries — healthcare, finance, and pharmaceuticals may require PDF/A for compliance and record-keeping.
- EU public procurement — electronic invoicing and procurement documents are often required in PDF/A.
PDF/A versions
There are several versions of the PDF/A standard. The most commonly requested are:
- PDF/A-1 (ISO 19005-1:2005) — the original version, based on PDF 1.4. Most restrictive.
- PDF/A-2 (ISO 19005-2:2011) — based on PDF 1.7. Adds support for JPEG2000 compression, transparency, and layers. This is the most widely used version today.
- PDF/A-3 (ISO 19005-3:2012) — same as PDF/A-2 but allows embedding arbitrary file attachments (such as the original Word document or XML data).
The PDF/A Conversion tool produces PDF/A-2b compliant files, which satisfies the requirements of most institutions and systems.
What changes during conversion
When you convert a regular PDF to PDF/A, the following happens:
- All fonts are embedded (if they were not already).
- Color spaces are standardized with an embedded ICC profile.
- Metadata is added in XMP format.
- Any JavaScript, form actions, or multimedia elements are removed.
- Encryption is removed (PDF/A cannot be encrypted).
The visual appearance of the document should remain the same. Text, images, and layout are preserved. The file size may increase slightly due to embedded fonts and color profiles.
Practical tips
- Convert as the last step — do all your editing, merging, or compressing first, then convert to PDF/A. Post-conversion edits might break compliance.
- Check for interactive elements — if your PDF has fillable forms, fill them out before converting. The form fields will be flattened into static content.
- Review the result — the tool shows a preview so you can verify that the converted document looks correct before submitting it.
- Combine with compression — if the PDF/A file is too large, compress it first (before conversion), as PDF/A conversion may increase file size slightly.
Is my PDF already PDF/A?
Most PDF viewers do not clearly indicate whether a file is PDF/A. Adobe Acrobat shows a blue bar at the top of compliant files. If you are unsure, the safest approach is to run the file through the conversion tool — if it is already compliant, the conversion will have minimal effect.