Fix Adobe Acrobat PDF File Size Increase After Digital Signature
Question details
The user needs to understand why adding a digital signature causes a massive file size increase and how to prevent this behavior to keep the document lightweight.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Applying a digital signature to a small PDF document.
- Observed behavior
- The PDF file size drastically inflates from a few kilobytes to several megabytes immediately after the digital signature is applied.
Verify with your IT or compliance department whether your organization strictly requires certificate revocation lists (CRL) to be embedded within digitally signed documents.
Disable Signature Revocation Status Embedding in Acrobat
Prevent Adobe Acrobat from embedding bulky Certificate Revocation Lists (CRL) into the PDF when signing.
The massive increase in file size is typically caused by Acrobat embedding a Certificate Revocation List (CRL) alongside your signature. This extra data ensures offline validation but bloats the file. By clearing this preference, the signature remains valid, but the system won't attach the large revocation dataset to the PDF.
Launch Adobe Acrobat, click on the 'Edit' menu at the top of the window, and select 'Preferences' from the dropdown list.
In the Preferences dialog box, select 'Security' from the left-hand category pane, then click on the 'Advanced Preferences' button.
A new window will appear. Click on the 'Creation' tab to view settings related to generating digital signatures.
Locate and uncheck the box labeled 'Include signature’s revocation status when signing'.
Click 'OK' on both dialog boxes to apply the changes. Open your original, unsigned document and sign it again to verify the reduced file size.
Digitally Sign PDFs Efficiently with WPS Office
If you want to avoid complex configuration menus while keeping your documents small, WPS Office offers a streamlined PDF editor. You can securely apply digital signatures without unnecessary backend data bloating your file size.
- 1. Open Your PDF: Launch WPS Office and open the PDF document you need to sign.
- 2. Access the Protect Tab: Click on the 'Protect' tab located on the top navigation ribbon to reveal security tools.
- 3. Apply Signature: Click on 'Sign Document' to easily create, import, or place your secure digital signature onto the page.
- 4. Save the Document: Save your PDF. WPS handles signature data efficiently, ensuring your file remains easy to share via email.
Frequently Asked Questions
What is a Certificate Revocation List (CRL) in a PDF?
A CRL is a backend list of digital certificates that have been invalidated by the issuing authority before their expiration date. Acrobat embeds this data by default to allow offline verification of a signature's validity, which significantly inflates the file size.
Will disabling revocation status invalidate my digital signature?
No. Your digital signature remains perfectly valid and secure. Disabling the feature simply means that anyone attempting to verify the signature must have an active internet connection so their software can check the revocation status directly with the certificate authority.
Can I compress the PDF file after adding a digital signature to reduce its size?
No. Compressing, editing, or otherwise altering a PDF document after applying a digital signature will break the document's structure and invalidate the signature. You must optimize the file size or adjust signing preferences before the signature is applied.
Does the visual appearance of my digital signature cause the file size increase?
Usually, no. The visual representation of a signature, such as a scanned image of your handwriting or typed text, typically only adds a few kilobytes to the document. Megabyte-level size jumps are almost exclusively caused by embedded security data like CRLs.
