What Is PDF/A, and Do You Actually Need It?
PDF/A is a PDF with the things that break over time removed. That is the whole idea. If you have ever opened a ten-year-old document and found the text replaced with boxes, you have seen the problem it exists to solve.
What PDF/A changes
- Fonts must be embedded. A document that relies on a font being installed on the reader's machine may look wrong in twenty years; one that carries its own fonts cannot.
- Colour must be defined unambiguously. Output intent and colour profiles are required so a colour does not drift depending on the device.
- No encryption. An archive must be openable without a password, so PDF/A forbids encryption.
- No audio, video or JavaScript. Anything that needs software to play is not archival.
- Transparency and layers must be flattened in the stricter levels, because they resolve differently in different renderers.
The levels that matter
- PDF/A-1 (2005): the strict original. Based on PDF 1.4, still the most widely demanded by archives.
- PDF/A-2 (2011): allows transparency and JPEG2000, and lets you embed other PDF/A files. Looser, more practical.
- PDF/A-3 (2012): PDF/A-2 plus the ability to attach files — for example an invoice PDF with the source XML attached. Increasingly required for electronic invoicing in parts of Europe.
- PDF/A-4 (2020): updated for modern PDF 2.0. Rarely required yet.
When it is genuinely required
- Public sector archives and government e-filing systems that state PDF/A explicitly in their submission rules.
- Long-term institutional archives — libraries, universities, courts, medical records.
- Electronic invoicing standards that name PDF/A-3, particularly in the EU.
- Anywhere a contract or regulation says "PDF/A" in writing.
When it is a waste of time
Everyday sharing. A colleague opening a report does not need PDF/A. Converting costs time and slightly increases file size.
Design work and print files. PDF/X is the print standard; PDF/A is for archives. They are not interchangeable.
Documents that need a password. PDF/A cannot be encrypted, so you cannot have both.
A document you are still editing. Convert to PDF/A at the end of the process, not the middle.
Convert and verify
- Convert with the PDF to PDF/A tool, choosing the level your recipient asked for.
- Open the result and check the text is still selectable — that confirms the font was embedded, not rasterised.
- Check the page count and the images.
- Note that file size usually grows, because embedding fonts adds data. That is expected.
- If a portal rejects the file, check which level it wants. Submitting A-2 where A-1 is required is a common rejection.
Privacy
Archival documents are, by definition, the ones being kept for decades — contracts, deeds, medical records, filings. Uploading them to a conversion service for a format change is a poor trade.
A browser-based converter performs the conversion on your own device. Nothing is uploaded, which matters most for exactly the documents PDF/A is used on.