# Want to understand the API transection and charges

**URL:** <https://pdfjs.community/t/want-to-understand-the-api-transection-and-charges/2770>\
**Category:** Technical Support\
**Created:** [August 8, 2023, 9:38pm UTC](https://pdfjs.community/t/want-to-understand-the-api-transection-and-charges/2770 "2023-08-08T21:38:05Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![schoolio](https://avatars.discourse-cdn.com/v4/letter/s/bc8723/32.png) [@schoolio](https://pdfjs.community/u/schoolio)\
**Post date:** [August 8, 2023, 9:38pm UTC](https://pdfjs.community/t/want-to-understand-the-api-transection-and-charges/2770/1 "2023-08-08T21:38:05Z")

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**Which product are you using?**  
PDF.js Express Plus

**PDF.js Express Version**

**Detailed description of issue**  
I want to understand more about the API transections.  
I get charged extra each month based on the api transection.

When I checked the number of total transections from the profile, below are the number of actions for client and server.  
Client - 13 Monthly - 21516 All time  
Server - 0 Monthly - 0 All time

- We are using client api keys for download pdf, because it is managed by our application, could this be included in above api transections?
- Is there something else I need to understanding?

**Expected behaviour**  
{Provide a screenshot or description of the expected behaviour}

**Does your issue happen with every document, or just one?**  
{Answer here}

**Link to document**  
{Provide a link to the document in question if possible}

**Code snippet**  
{Provide a relevant code snippet}

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**Author:** ![tgordon](https://avatars.discourse-cdn.com/v4/letter/t/aca169/32.png) [@tgordon](https://pdfjs.community/u/tgordon)\
**Post date:** [August 8, 2023, 9:55pm UTC](https://pdfjs.community/t/want-to-understand-the-api-transection-and-charges/2770/3 "2023-08-08T21:55:11Z")

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Hello schoolio,

We have more information on the REST API here:

> **[PDF.js Express Utility API | Documentation](https://pdfjs.express/documentation/utils)**

You only need to use it for:

- Merging Annotations
- Extracting Annotations
- Set Annotations
- Watermark Document

Best regards,  
Tyler

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<div class="post-metadata">

**Author:** ![schoolio](https://avatars.discourse-cdn.com/v4/letter/s/bc8723/32.png) [@schoolio](https://pdfjs.community/u/schoolio)\
**Post date:** [August 9, 2023, 1:28pm UTC](https://pdfjs.community/t/want-to-understand-the-api-transection-and-charges/2770/4 "2023-08-09T13:28:53Z")

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Perfect, thanks tgordon 🙂.