Converting PDF to PDF/A-3u

Xodo PDF Studio has the ability to convert files in the PDF/A-3u format. PDF/A-3u is a strict subset of the ISO PDF specification used to create archival versions of documents with the intent that they will always render exactly the same as when they were saved.

When converting to Xodo PDF Studio will attempt to convert the PDF to the PDF/A-3u format by making the following changes to the document

  • Graphics will be converted to a device-independent format. If any device dependent color spaces are used, they will be defined by embedding a color profile for these color spaces.
  • Fonts will be embedded with Unicode support.
  • Unsupported annotations (e.g., video, audio, 3D) will be removed.
  • JavaScript (mostly used in Forms) will be removed.
  • External hyperlinks will be removed.


How to Convert a PDF to PDF/A-3u

  1. Open the PDF Document you wish to convert
  2. Go to the Convert Tab > PDF/A > PDF/A-3u on the menu
  3. A dialog will be displayed showing the changes that will be made to the document
  4. Choose a file name and location to save the document
  5. Click Save to convert the document to PDF/A-3u

    If any problems occur during preflight conversion, a results list will be displayed showing the content items that could not be fixed. If the conversion completes successfully the problems list will not be shown and the newly converted document will be opened.

PDF/A Conversion Results

Xodo PDF Studio will attempt to convert every file but due to the PDF/A-3u requirements some files may not be able to be converted. If the conversion fails a dialog will be displayed showing the reasons that the conversion failed.

Results List - Lists any content in the document that was not converted with the selected profile.

- Items that could NOT be fixed by Xodo PDF Studio.

- Items that were not fixed due to user settings in PDF/A Preferences.

Expand - Expands the results tree to show all preflight error results

Collapse - Collapses the results tree to only show the preflight error categories

Print - Prints the entire tree exactly as it is displayed in the preflight results list

Note: When the conversion is successful no dialog will be displayed as the conversion process completed and saved the new document correctly

Unsupported Features in PDF/A-3u Conversion:

Below is a list of features that may cause errors during the PDF/A-3u conversion.

  • The PDF document contains non-embedded fonts that do not exist on the system
    • Workaround: There is no workaround for fixing this other then recreating the PDF document using different fonts.
  • The PDF document is secured / encrypted with passwords and permissions.
    • Workaround: Users should clear any security on a document before running PDF/A conversion.
  • The PDF documents has user rights enabled.
    • Workaround: Users should clear user rights before running PDF/A conversion.
  • The PDF document contains a digital signature. Converting to PDF/A would invalidate any digital signature.
    • Workaround: Users should clear or remove digital signature fields before running PDF/A conversion.
  • The PDF document contains unsupported PDF commands or operators. Often these documents can not render in Xodo PDF Studio or will have pages that do not render properly.
    • Workaround: Users may be able delete the invalid pages.

Verify that Existing Document is PDF/A-3u Compliant

Viewing the Document or Document Properties

When opening a document that is PDF/A-3u compliant a blue notification "This document is tagged as PDF/A-3u compliant" will be displayed at the bottom of the Xodo PDF Studio window. You can also confirm the PDF/A-3u compliance in the document properties dialog.

  1. Go to File Tab > Properties from the menu or using the shortcut keys Ctrl + D (⌘ + D on Mac).
  2. Click on the General Tab
  3. In the lower right corner of the general document properties there will be a "PDF/A" label that will show "Yes" if the document meets the PDF/A-3u compliance standards

Using Preflight Verification

You can also use the PDF/A-3u Preflight Validation to verify that the document complies with the PDF/A-3u standards