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Request a Feature Report a Bug
Completed
Last Updated: 19 Aug 2026 10:45 by ADMIN
Release 2025.1.205 (2025 Q1)
ADMIN
Deyan
Created on: 16 Nov 2016 18:09
Category: PdfProcessing
Type: Feature Request
67
PdfProcessing: Introduce API allowing to optimize and reduce the size of existing PDF files

For example, when some PDF file has uncompressed contents we may import it and apply better compression to the stream objects. Ensure that all the content inside the document is compressed.

Currently, we have the following options for PDF export optimizations:

14 comments
ADMIN
Yoan
Posted on: 19 Aug 2026 10:45

Hello Ben,

Thank you for reaching out and for bringing this to our attention. I understand how frustrating it can be when you encounter unexpected results.

Before I can provide a definitive answer, I’ll need to reproduce and examine the same behavior on my end. Could you please provide a step-by-step project, including the complete workflow and any relevant details, that consistently reproduces the issue? This will allow me to investigate the behavior more accurately on my end.

Also, since this is currently a public feature request thread that contains other discussions and topics, I’d recommend opening a separate support ticket for the PdfProcessing library, specifically for this issue. Keeping the investigation in a dedicated ticket will help us avoid mixing different topics and will also provide a more appropriate place to share project files, logs, screenshots, or other resources that may be needed for the investigation.

Once the support ticket is created, please attach the complete reproducible project and any relevant description and resources there, and I’ll be happy to take a closer look.

Thank you for your understanding and cooperation.

    Regards,
    Yoan
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    Ben
    Posted on: 18 Aug 2026 13:58
    Hello,

    We are having issues when we export PDF with isEncrypted and a password.

    When user remove password and try to save pdf in ADOBE PRO they always have error 

    It was working with version 2025.2.250 but now we always have this error with any new version.

    Yes we can disable the Optimize for Web option in ADOBE and it will work but that is not a valid option for our customers.

    We have try many different things even this example but still stuck with this error.

    Is there a solution for this ? 
    ADMIN
    Peshito
    Posted on: 17 Dec 2024 08:00

    Hello,

    APIs for optimizing and reducing the size of PDF files are implemented and can be referred to in the item's description. We are closing this request as it is now completed. We will continue to optimize the file size further. In case you experience any issues or concerns, please let us know or refer to our Knowledge Base articles:

    Regards,
    Peshito
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    ADMIN
    Dimitar
    Posted on: 09 Feb 2023 07:59

    Hi Dusty,

    Thank you for your feedback. 

    I believe that it would be better to open a new support ticket and attach the files that are causing the undesired behavior. In addition, add your code since there is more than one way to merge the files. This will allow us to investigate your exact case and determine if there is an issue with our product. 

    Let me know if I can assist you further.

    Regards,
    Dimitar
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    Dusty
    Posted on: 08 Feb 2023 20:36
    This seems like a welcome add.  I use the merge feature of PdfProcessing, and sometimes pdf's won't merge at all.  I've always assumed it's because they are too large or there's some objects embedded in them that are causing that.  But here's the thing - if I manually resave them using Microsoft Print To PDF, those PDF's will always merge.  So, you might look at whatever that MS library is doing.  Of course, I know you can do even better, because you're Telerik!
    ADMIN
    Martin
    Posted on: 07 Jan 2021 11:25

    Hello Cüneyt,

    In order to reuse the embedded fonts from one of the merged documents, you can check the project with a possible workaround I attached to this feature request. I should mention the suggested workaround doesn't cover all possible cases (e.g. if there are fonts with a common name but different font sets (modified fonts or font subsets) this may lead to missing/different characters in the produced document). So in order to use this workaround, you will need to ensure the font names are unique for every different font.

    If this not solves your case, I would like to ask you to provide us with the documents causing this behavior in order to deeper investigate it (for example by opening a new private support ticket)? I must assure you we treat all client files in a strictly confidential manner and for testing purposes only.

    Regards,
    Martin
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    Maximilian
    Posted on: 05 Jan 2021 10:19

    Hi Martin,

    the reuse of embedded fonts in pdf merging will be a part of the solution but cannot be the last bugfix. And it is a buggy behaviour.
    We're currently evaluating the pdf library to create pdf files from html-files. We've encountered an average increase in the pdf filesize regarding to the compressed one between 1200% and 2000% !!!
    We will have to implement an additional  library for compression, or switch to another library.
    This ticket has been maturing from 2016 to 2021 now. When finally do you plan the compression fix?

    Regards
    Cüneyt

    ADMIN
    Martin
    Posted on: 21 Dec 2020 18:34

    Hi Fadi,

    Thank you for the feedback. I logged a feature request on your own in our backlog to implement such consolidation of fonts: Provide a mechanism to reuse an already embedded font when merging documents with the PdfStreamWriter. You can upvote the task and subscribe to it so you can receive updates about status changes.

    In appreciation for bringing this to our attention, I updated your Telerik points.

    Regards,
    Martin
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    Fadi
    Posted on: 18 Dec 2020 13:36

    When merging a 400kb pdf 100 times, the result is 40MB, using a different component the result is 1.4MB.

    Seems the embedded fonts are getting embedded repeatedly instead of being consolidated.

    ADMIN
    Martin
    Posted on: 17 Sep 2020 10:06

    Hi Neil,

    Thank you for the feedback. We will take it into consideration when the development of this feature begins. Meanwhile, make sure you cast your vote for the implementation as well as subscribe to the task by clicking the Follow button.

     I apologize for the inconvenience this missing functionality might be causing you. 

    Regards,
    Martin
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    Neil N
    Posted on: 16 Sep 2020 19:45
    Doubling the size of a PDF when a few form fields are filled out is pretty bad.
    ADMIN
    Tanya
    Posted on: 08 Mar 2018 09:23 
    Thank you for the feedback. Make sure to cast your vote for the implementation of the item and continue following it so you can get a notification about status changes on it.
    Chris
    Posted on: 01 Mar 2018 23:50 
    Would be very interested in this.  Any PDF Processing implementation should have the ability to compress and optimize, especially when needing to send it to a web service.
    Nick
    Posted on: 19 Aug 2017 11:29 
    This would be a good feature.
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