Loading large documents (DOCX import and SFDT) – best practices?

[Lion Tales]

Hi,

I’m using the Document Editor in an Angular app with DocumentEditorContainer from @syncfusion/ej2-angular-documenteditor (v32). I load documents either as SFDT (open(sfdt)) or as DOCX via blob (open(blob)).

For large documents (e.g. 400+ pages), loading and layout can take around 1–2 minutes for both SFDT and DOCX. I’d like to know:

SFDT: Are there recommended approaches for loading large SFDT (e.g. chunking, lazy layout, or specific options) to improve perceived performance?

DOCX import: Same question for large DOCX files opened with open(blob) – any best practices or APIs to speed up import/layout?

I’m on Syncfusion EJ2 Document Editor 32.1.x with Angular. Thanks for any guidance or sample approaches.

[Akshaya Arivoli]

Hi Lion,

We are currently checking your query based on the information provided. We will get back to you with further updates on February 3,2026

Regards,

Akshaya

[Akshaya Arivoli]

Hi Lion,

In the Document Editor, the document loading time depends on the content present within the document.

Regarding SFDT:

When an SFDT document is loaded, the document is loaded, after which it is processed to perform layout calculations. Once the layout processing is completed, the content is rendered in the Document Editor UI. Therefore, the overall rendering time varies based on the document’s content.

Regarding DOCX:

When a DOCX document is loaded, it is first sent to the server, where it is processed and converted into SFDT. The converted SFDT is then sent back to the client. On the client side, layout processing and content rendering are performed. Therefore, the overall rendering time varies based on the document’s content.

Asynchronous Loading

To overcome this, we have introduced asynchronous loading in the Document Editor. When a document is loaded asynchronously, you can begin reading and scrolling through the content before the loading is fully completed. Please note that we can view the pages already loaded, but all other interactions remain restricted until all pages finish loading.

Code snippet for asynchronous loading

 

container.documentEditor.openAsync(JSON.stringify(sfdt));

We have also shared a sample for your reference. Run the sample and click on 'Open Document'

Sample : Twtekvxz (duplicated) - StackBlitz 

Please try with the provided details and if you still need assistance revert with more details and the input document. These details will be helpful for us to investigate further and assist you better.

Regards,

Akshaya