Power BI Desktop - Web Data Import size limitations

Hi, Diplodicus 

Power BI has a maximum column limit of 16,000 columns across all tables in the semantic model. If a large file exceeds this limit when you try to import all your tables and columns, it could be one of the reasons for the issue. For more information, see Data source limits for the Power BI service:

Data sources for the Power BI service - Power BI | Microsoft Learn

While column limits are a definite constraint, large files can also present challenges due to memory limitations, especially if the data transformation steps in Power Query are complex. The performance of Power BI Desktop can be significantly impacted by the available RAM, especially when working with large datasets.

If possible, try to reduce the complexity of the data you're importing. This may involve filtering out unnecessary columns or tables before importing data into Power BI. You can do this by editing the .htm file or by using preliminary data processing steps outside of Power BI.

If your data allows, consider splitting larger files into smaller chunks. This can mean splitting the data into multiple .htm files based on logical partitions, and then importing them into Power BI individually.

If you are experiencing memory limitations, increasing the RAM on your system may help. Also, make sure you're using the 64-bit version of Power BI Desktop, as it makes better use of system resources than the 32-bit version.

Make sure Power BI Desktop is up to date. Newer versions often come with performance improvements and bug fixes that may fix your problem.

For more detailed guidance on working with web data in Power BI Desktop:

Tutorial: Import and analyze data from a webpage - Power BI | Microsoft Learn

How to Get Your Question Answered Quickly 

Best Regards

Yongkang Hua

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.