PDF/A is a standardized version of the PDF designed for long-term archival. Unlike regular PDFs, PDF/A ensures your documents remain accessible for decades, making it crucial for legal compliance.
This article covers everything you need to know about PDF/A, from different formats to practical applications in legal, government, and document storage settings.
What Is a PDF/A?
PDF/A is an ISO-standardized version of the PDF file format, designed for long-term digital recordkeeping. It ensures that documents continue to display consistently, regardless of the software, hardware, or operating system.
The “A” in PDF/A stands for “Archive,” and refers to its purpose of preserving electronic documents. It works by embedding all the necessary components in a document and restricting features that may not be reliably rendered or preserved over time, such as multimedia.
Additionally, PDF/A works well for scanned PDFs because it preserves the quality of image-based content. To make these scans searchable, you can apply OCR (Optical Character Recognition). This added feature turns images of text into actual text without affecting the file’s compliance with PDF/A standards.
When and Why to Use PDF/A?
Here’s a detailed overview of when and why to use the PDF/A format:
- Storing legal documents. Legal files generally serve as evidence in proceedings, audits, and compliance reviews, so they must remain unchanged over time. PDF/A helps ensure this by preserving the files’ visual fidelity.
- Archiving government records. Many federal and state agencies around the world use PDF/A for certain categories of permanent records to ensure compliance with retention requirements. For example, all Danish government bodies have been required to save non-editable documents in PDF/A format since April 2011.
- Publishing scientific and academic work. To make sure citations, references, and formatting in papers remain accessible to future researchers, publishers often choose PDF/A. It preserves layout, figures, fonts, and metadata, ensuring papers display consistently over time.
- Preserving business contracts and records. Typically, these have legal, financial, and operational significance and may need to be accessed years later during audits, disputes, or regulatory checks. PDF/A guarantees they remain as they were originally created, unaltered, and complete.
What Are the Key Features of PDF/A?
The key features of PDF/A include:
- Self-contained files: All fonts, images, color profiles, and metadata are embedded within the document. This ensures the file can be opened and viewed exactly as intended, even years later, without relying on external resources.
- Static content only: PDF/A prohibits elements like audio, video, and JavaScript to maintain long-term reliability. By limiting the file to static content, it reduces the risk of compatibility issues and helps preserve the document’s integrity over time.
- Device-independent display: PDF/A makes sure that the layout, fonts, colors, and overall appearance of a document remain the same, no matter which system or software is used to open it. This is crucial for preventing misinterpretation and issues like PDF missing text.
- ISO standard compliance: PDF/A follows the ISO 19005 standard, which sets clear guidelines for archiving electronic documents. By following the ISO standard, PDF/A is a trusted format for governments, legal institutions, businesses, and archives around the world.
What’s the Difference Between PDF and PDF/A File Format?
PDF and PDF/A file formats differ in terms of purpose, editability, use cases, viewer compatibility, font handling, dynamic elements, and encryption.
Here is a detailed breakdown of regular PDF vs. PDF/A :
| Feature | Regular PDF | PDF/A |
|---|---|---|
| Purpose | Designed for general document sharing and viewing | Designed for long-term digital recordkeeping |
| Editability | Can be edited, annotated, or signed digitally | Cannot be altered |
| Use Case | Used for forms, reports, brochures, and manuals | Used for legal, scientific and academic, and business documents |
| Viewer Compatibility | May vary depending on features and devices | Ensures consistent display across all compliant viewers |
| Fonts | May use external fonts | Embeds all fonts |
| Dynamic elements | Supports audio, video, JavaScript, and interactive objects | Doesn’t allow dynamic content |
| Encryption | Supports encryption and password protection | Prohibits encryption |
4 Types of PDF/A Formats
There are four types of PDF/A formats:
#1. PDF/A-1
Based on PDF 1.4, PDF/A-1 is the original archival standard introduced in 2005. It provides basic archival features with two conformance levels:
- PDF/A-1a. The ‘a’ stands for ‘accessible’; it ensures full text accessibility.
- PDF/A-1b. The ‘b’ stands for ‘basic’; it focuses on preserving a document’s visual appearance, but it excludes transparency, layers, and advanced graphics features.
#2. PDF/A-2
This document retention format is based on PDF 1.7 and was released in 2011. It has expanded capabilities while maintaining archival integrity.
More specifically, PDF/A-2 supports JPEG 2000 compression, transparency effects for graphical elements, and digital signatures. Additionally, PDF/A-2 allows for PDF/A-compliant file attachments, PDF packages, and complex portable collections.
There are three levels of conformance:
- PDF/A-2a. The ‘a’ stands for ‘accessible’; it provides full accessibility features and structural tagging.
- PDF/A-2b. The ‘b’ stands for ‘basic’; it ensures visual reproduction but does not preserve the document’s structural or semantic elements.
- PDF/A-2u. The ‘u’ stands for ‘Unicode’; it guarantees that all text has Unicode mapping for reliable text extraction.
#3. PDF/A-3
Released in 2012, PDF/A-3 includes all PDF/A-2 features plus the ability to embed any file format within the PDF/A document. This flexibility allows organizations to include source files, spreadsheets, or other supporting documents while maintaining PDF/A compliance. As with PDF/A-2, PDF/A-3 has three levels of conformance: PDF/A-3a, PDF/A-3b, and PDF/A-3u.
#4. PDF/A-4
Unlike previous PDF/A standard versions, PDF/A-4 allows certain interactive features, including form fields and JavaScript. However, JavaScript must be stored as embedded data and cannot run automatically.
Sound, screen, and movie annotations are not allowed in PDF/A-4, and 3D and rich media annotations are only allowed in a specific profile called PDF/A-4e, which is designed for engineering documents.
Another change is that PDF/A-4 does not use the A, B, or U conformance levels. Previous versions used these levels to define accessibility and text recovery standards. Instead, PDF/A-4 encourages the use of PDF/UA (ISO 14289) standards for accessibility.
How to Create a PDF/A File?
To create a PDF/A file, you can use PDF software, convert existing PDFs, export from MS Word or other apps with “Save as PDF/A,” or use an online PDF/A converter.
- PDF software. Programs like Adobe Acrobat, PDF24, and Foxit include built-in options to create or convert documents to PDF/A. These tools often come with validation features to ensure compliance with the appropriate PDF/A standard.
- Converting existing PDFs. You can convert a PDF to PDF/A by using supported PDF software. Most tools offer conversion settings that let you choose the PDF/A conformance level (e.g., PDF/A-1b or PDF/A-2u) during the export process.
- Exporting from applications. Many programs, such as Microsoft Word, Excel, and PowerPoint, include a “Save as PDF/A” under their export settings. You can conveniently generate compliant files directly from your source documents this way.
- Using an online PDF/A converter. There are various online PDF tools that convert standard PDFs to PDF/A format. These can be useful for quick conversions, though they may offer limited customization or validation.
How to Edit a PDF/A File?
To edit a PDF/A file, you can use a professional PDF editor, convert PDF/A to standard PDF, or open the file in Microsoft Word.
#1. Use a Professional PDF Editor
You can use professional PDF editors to modify PDF/A files; some may prompt you to temporarily disable PDF/A mode before making changes. After editing, you must revalidate the file to ensure it still meets PDF/A requirements.
Here are some editors and how they compare:
| Software | PDF/A Editing Support | PDF/A Validation & Preflight | Font Embedding Control | Save as PDF/A | Platform |
|---|---|---|---|---|---|
| Adobe Acrobat Pro | Yes | Yes | Yes | Yes | Windows, macOS |
| Foxit PDF Editor | Yes | Yes | Yes | Yes | Windows, macOS |
| PDF-XChange Editor | Yes; editing with PDF/A mode | Limited; via add-ons | Yes | Yes | Windows |
| Nitro PDF Pro | Yes; after converting to PDF | No | Yes | Yes | Windows, macOS |
| PDF24 Creator | Limited; mostly conversion-based | No | No | Yes; basic PDF/A creation | Windows |
#2. Convert PDF/A to Standard PDF
You can convert a PDF/A file to a regular PDF, make your edits, and then convert it back to PDF/A. Just make sure to check if the fonts, color settings, and PDF metadata meet PDF/A standards.
To do this, run compliance preflight checks; usually, professional PDF software displays detailed error reports with suggested fixes and page numbers.
#3. Open in Microsoft Word
You can open a PDF/A file in Microsoft Word through the Open dialog and convert the file into an editable Word format. After editing, use the “Save as PDF/A” function to export the file.
However, keep in mind that the conversion process can lead to formatting inconsistencies, font substitutions, and loss of precise positioning. You will need to spend time reformatting, especially if your file contains complex tables, images, and special elements.
Prepare & Polish Your PDFs with PDF.net
If you want to edit your PDF after converting it from the PDF/A format, use PDF.net. This handy browser-based tool will provide you with a full suite of tools. For example, you can rearrange pages, add annotations or highlights to them, and add page numbers easily.
Furthermore, if you want to compress the document without losing quality, that’s possible with PDF.net as well.
Also, your information is protected every step of the way; PDF.net uses encrypted connections. Whether you are handling PDF contracts, reports, or academic papers, you can securely prepare and polish your documents before converting them.
Final Thoughts
A PDF/A is a subset of the PDF format that complies with the ISO 19005 standard for archiving electronic documents. It is commonly used for storing legal, government, academic, and business files that must remain accessible over time.
With four PDF/A standard versions, each building on the last, it offers increasing support for modern workflows. Creating a PDF/A file is straightforward with professional PDF tools, MS Word or other software that supports PDF/A export, and online converters.
What is PDF/A FAQs
#1. Is PDF/A the same as a regular PDF?
PDF/A is not the same as a regular PDF; it is a specialized subset of PDF specifically designed for archival purposes. A PDF/A file is self-contained with embedded resources for long-term accessibility.
#2. Can I open a PDF/A with a regular PDF reader?
You can open a PDF/A file with a regular PDF reader, including browser-based ones. This document retention format maintains backwards compatibility, so the file can be accessed across different platforms and devices.
#3. Is PDF/A searchable?
Yes, a PDF/A file is searchable when it contains text; this format preserves text data and metadata, allowing you to search within the file using standard search functionality.
#4. Can I edit a PDF/A?
You can edit a PDF/A, but editing often requires converting the file or using advanced tools. PDF/A is designed for preservation, not modification; therefore, edits must be made carefully to maintain compliance.
#5. What does “PDF/A compliant” mean?
It means that a PDF file meets the technical and structural requirements set out in the ISO 19005 standard for long-term archival. A PDF/A-compliant file is self-contained, static, and structured for digital recordkeeping.