Which PDF Standard Is Better to Choose

For some tasks, certain PDF standards will fit better or vice versa worse. In this article, we will try to determine which PDF standards for which cases it makes sense to choose.

PDF 1.7 vs PDF 2.0

At the moment there is no big difference between Aspose.Words’ PDF 1.7 and PDF 2.0 output.

Aspose.Words PDF 2.0 output just allows to use some new features, such as a new encryption algorithm. But there may be difficulties in handling of PDF 2.0 output in older PDF viewers. So, PDF 2.0 should be used if new features are needed. Otherwise, PDF 1.7 should be used.

This may be reconsidered later.

When to Use PDF/A and Which Version

PDF/A is a format for archiving and long-term preservation. Generally it is required by authorities, archives, libraries, and so on. So, the use of PDF/A compliance is dictated by the requirements of the PDF consumer. And if PDF consumers do not require it, then it should not be used.

The PDF/A version should be selected to be the highest acceptable for the consume, since higher versions are more reliable for Aspose.Words PDF/A output. However, the conformance level for PDF/A-1 or PDF/A-2 should also be selected according to consumer requirements. Thus, if level A is required, then it should be used, and if level B/U is required, then both level B/U and level A could be used.

Note that level A documents are accessible but take more space than level B/U documents.

When to Use PDF/UA

PDF/UA should be used if PDF consumers require it. Also it could be used if you just need the accessible PDF output, but it will take more space compared to regular PDF output.

FAQ

  1. Q: What is the practical difference between PDF 1.7 and PDF 2.0 when using Aspose.Words?
    A: Functionally they are very similar; PDF 2.0 adds support for newer features such as an advanced encryption algorithm. Use PDF 2.0 only when you need those features, because older PDF viewers may have compatibility issues.

  2. Q: When should I choose PDF/A over a regular PDF?
    A: Choose PDF/A when the document must be archived for long‑term preservation or when a regulatory body requires it. Select the highest PDF/A version that the consumer accepts, as newer versions provide more reliable output.

  3. Q: How do I decide which PDF/A conformance level (A, B, or U) to use?
    A: Level A provides full accessibility and is required when the consumer needs it. Levels B and U are lighter and produce smaller files; they are suitable when only visual fidelity (B) or basic accessibility (U) is required.

  4. Q: What are the benefits of using PDF/UA, and does it increase file size?
    A: PDF/UA ensures the PDF meets accessibility standards (WCAG 2.0, Section 508). It is ideal when accessibility is a requirement, but the output will be larger than a standard PDF because of the additional tagging and metadata.

  5. Q: Is there any licensing impact when switching between PDF standards in Aspose.Words?
    A: No. All PDF standards (PDF 1.7, PDF 2.0, PDF/A, PDF/UA) are fully supported under a regular Aspose.Words license. The license does not need to be changed when you select a different PDF standard.

Conversion to PDF/A and PDF/UA Working with PDF/A or PDF/UA