What does PDF/A mean for your PDF?
PDF/A forbids what ages badly: fonts that are not embedded, encryption, JavaScript, audio and video, and external links for content. It requires embedded color profiles and standards metadata, so the file renders the same in fifty years as today.
Courts, tax authorities and university repositories often demand it. The variants matter: PDF/A-1b is the strict baseline, PDF/A-2 allows JPEG 2000 and transparency, and PDF/A-3 allows attachments, which is how e-invoicing formats ride inside a readable invoice.
To be clear about this site: the tools here do not produce PDF/A-conformant files, and nothing claims to. Word, LibreOffice and Acrobat all export it directly, which is the reliable route when a portal insists.
How do you tell whether a file really is PDF/A?
Claiming the format and conforming to it are different things. Acrobat shows a blue bar across the top of a document it recognizes as PDF/A; free validators such as veraPDF check a file properly and list every rule it breaks, which is what a submissions portal will be doing at the other end.
Common reasons a file is rejected: a font that was referenced rather than embedded, encryption left on, a color profile missing, or transparency in a logo that PDF/A-1 does not allow.
Converting an existing PDF usually works when the document is simple, and usually fails when it is not — the converter cannot embed a font it does not have, and it cannot invent a color profile. Exporting to PDF/A from the original Word or design file is the route that reliably passes.
The tools on this site do not produce PDF/A-conformant files. Word, LibreOffice and Acrobat all export it directly, and that is what to use when a portal insists.