Government departments, legal archives, research institutions, ISO standards — anywhere documents need to be readable in 50 or 100 years, they're stored as PDF/A. Regular PDFs aren't guaranteed to render the same forever.
What PDF/A is
PDF/A (PDF for Archive) is an ISO standard (ISO 19005) for long-term preservation of electronic documents. It's a stricter subset of PDF: no external dependencies (everything embedded), no encryption, no JavaScript, no audio/video, no transparency in some sub-standards.
The result: a PDF that's guaranteed to render the same on any conforming viewer, decades into the future.
PDF/A flavours
PDF/A-1 (2005): the original standard, strictest. PDF/A-2 (2011): supports JPEG2000, transparency, layers. PDF/A-3 (2012): allows embedded non-PDF files. PDF/A-4 (2020): based on PDF 2.0.
For most archival use, PDF/A-1 or PDF/A-2 is what regulators specify. Check the requirement before converting.
Converting from Word
In Word: File > Save As > PDF > Options > ISO 19005-1 compliant (PDF/A). The output meets the standard.
For online conversion, Flint's Word to PDF standard output is regular PDF; for PDF/A specifically, convert in Word with the ISO option enabled, or use a dedicated archival conversion tool. Validate the output against a PDF/A validator (Veraform, online checkers) before submitting to archive.
What you give up
PDF/A requires all fonts embedded — so the output file is larger. It disallows transparency in older flavours, so certain visual effects degrade. It blocks interactive elements like form fields with scripts. For static archival, none of this matters; for interactive forms, PDF/A might not be the right target.
FAQ
Which PDF/A do I need?
Depends on the specifying authority. PDF/A-1b is the most common default; some archives now accept PDF/A-2u.
Will fonts be embedded?
Yes — PDF/A requires it. The PDF includes the font outlines for every used character.
Can I edit a PDF/A?
Editing breaks the conformance. After editing, re-validate or re-export as PDF/A.
Is PDF/A bigger than normal PDF?
Slightly — font embedding adds size. Usually 10–30% larger for typical documents.
Built to last. Export from Word with the PDF/A option set, or convert with Word to PDF and validate after.