PDF Tips PDF Basics What Is PDF/A?

What Is PDF/A and When Do You Need It?

The ISO standard for long-term document archiving — what it requires, when it's mandatory, and how to convert any PDF to PDF/A for free.

February 17, 2026 PDF Basics 7 min read
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Regular PDFs are great for sharing and viewing. But what about documents that need to be reliably readable in 50 years? Or legal filings that must meet court archiving standards? That's where PDF/A comes in — a specialized subset of PDF designed specifically for long-term preservation, with strict rules that guarantee the document will display correctly far into the future.

What Does the "A" in PDF/A Stand For?

The "A" stands for Archive. PDF/A (ISO 19005) is an ISO standard that defines which features of regular PDF are permitted in a document intended for long-term preservation. The goal is self-containment: a PDF/A file must carry everything needed to render it identically — regardless of what software, operating system, or hardware exists decades from now.

How PDF/A Differs from Regular PDF

PDF/A is a subset of PDF — it allows most PDF features but prohibits or restricts those that could compromise long-term readability:

FeatureRegular PDFPDF/A
Font embeddingOptionalRequired — all fonts must be embedded
Color spacesAnyMust be device-independent (ICC profiles required)
EncryptionAllowedProhibited — cannot be password protected
External contentAllowed (links to external resources)Prohibited — must be fully self-contained
JavaScriptAllowedProhibited
Audio/VideoAllowedProhibited
MetadataOptionalRequired (XMP format)

PDF/A Versions: A, B, U, E

PDF/A has several conformance levels:

  • PDF/A-1b — Basic level: ensures visual reproduction. Most common requirement for legal and government filing.
  • PDF/A-1a — Adds accessibility requirements: tagged structure, logical reading order, Unicode text mapping.
  • PDF/A-2 — Based on PDF 1.7; adds support for JPEG 2000 compression and digital signatures.
  • PDF/A-3 — Allows embedding of non-PDF files (e.g. XML, spreadsheets) within the PDF/A container.

For most archiving purposes, PDF/A-1b or PDF/A-2b is required. Check the specific requirement of your industry or institution.

When Is PDF/A Required?

PDF/A is mandatory or strongly recommended in several contexts:

  • Government and legal filings — many courts, agencies, and regulatory bodies require PDF/A for document submissions
  • Healthcare records — medical records that must be retained for decades often require PDF/A
  • Financial documents — auditing requirements in many jurisdictions specify archival-grade PDF
  • Academic publishing — some journals and institutional repositories require PDF/A for thesis submissions
  • Corporate compliance — companies subject to document retention regulations often convert records to PDF/A
  • Any document with a 10+ year retention requirement — regular PDF is not guaranteed to render correctly as software evolves

How to Convert a PDF to PDF/A at PDFToolShack

  1. Open the PDF/A Converter tool
  2. Upload your PDF
  3. Select the conformance level required (PDF/A-1b is the most common)
  4. Click Convert
  5. Download your PDF/A compliant file

Note: if your PDF is password protected, you'll need to remove the password first — encryption is not permitted in PDF/A.

Key Takeaways
  • PDF/A is an ISO archiving standard that ensures documents render identically for decades
  • It requires embedded fonts, device-independent colors, and no encryption or external dependencies
  • PDF/A-1b is the most common conformance level required by courts and government agencies
  • Required for legal filings, healthcare records, financial compliance, and long-term archiving
  • Password-protected PDFs must be unlocked before conversion to PDF/A
  • Convert any PDF to PDF/A free using PDFToolShack's PDF/A Converter

Convert your PDF to PDF/A free — right now.

ISO-compliant archival format. Select conformance level, convert, download.

PDF/A Converter Free