Limitations of px.imshow

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#5,479 4 comments 0 reactions 1 assignee View on GitHub

@feiler98 is already working on this.

Since Feb 4, 2026.

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Description

Dear plotly developers,

I wanted to know if there is a limit for the size of a heatmap generated with px.imshow()
I am currently using it for creating large heatmaps of 1,000+ rows and 10,000+ columns (with custom hovertemplate), but at a certain size saving it as plotly.offline.plot() as html file, the whole document is blank.

Is this a limitation of the plotting method and/or is there a setting that could be changed to increase the heatmap size and complexity (e.g. more information integrated into the hovertemplate)

I am looking forward to your reply!

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