PDF/A
An ISO-standardized variant of PDF designed for long-term archival — fonts are embedded, external dependencies are disallowed, and the file will render identically decades from now.
PDF/A is a specialized version of the PDF format designed for long-term archival. It is defined by the ISO 19005 standard. The core idea: a PDF/A file must be completely self-contained — everything needed to render it correctly has to live inside the file, with no external dependencies that could disappear in 20 years.
How PDF/A differs from regular PDF
- All fonts must be embedded. A regular PDF can reference fonts installed on the reader's system; PDF/A must ship the fonts with the file.
- No external content. JavaScript, external audio/video, and hyperlinks to files outside the PDF are not allowed.
- No encryption. A PDF/A file must be readable by anyone, anywhere, without a password.
- Color must be device-independent. Colors are defined in absolute color spaces so they render the same on any monitor or printer.
When to use PDF/A
Archival is the natural fit: legal discovery, regulatory submissions, research papers deposited in libraries, government records. Some jurisdictions legally require PDF/A for official records retained for decades.
Tools
- Convert a regular PDF to PDF/A — useful before filing a document for long-term storage.