# Dash renderer - slow?

**URL:** <https://community.plotly.com/t/dash-renderer-slow/85464>\
**Category:** Dash Python\
**Created:** [June 30, 2024, 6:41am UTC](https://community.plotly.com/t/dash-renderer-slow/85464 "2024-06-30T06:41:15Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mingw64](https://avatars.discourse-cdn.com/v4/letter/m/e19b73/32.png) [@mingw64](https://community.plotly.com/u/mingw64)\
**Post date:** [June 30, 2024, 6:41am UTC](https://community.plotly.com/t/dash-renderer-slow/85464/1 "2024-06-30T06:41:15Z")

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My app loads 3 dbc tabs, in each tab there is a dbc table. Each table includes about 50-500 simple html.P elements (number value and color background).  
Looking at dev tools network and performance tabs, I’m satisfied with my callback time and data transfer time, but rendering takes a very long time.

This is the performance chart:  
 ![image](https://us1.discourse-cdn.com/flex024/uploads/plot/original/3X/e/a/eadf118e6941559dff234fb3b6e4ccd0ce3423f8.png)  
The idle time, if I correlate correctly with the network tab, is the time it takes for the callback to run on the server and I’m ok with it. The question is - why is scripting taking so long?

Going deeper, it is all dash renderer?

 ![image](https://us1.discourse-cdn.com/flex024/uploads/plot/original/3X/a/b/ab7351daafbd7dab06ca0b2800576fde38ab2823.png)

Is this expected? I would expect a few hundred simple html elements are not too hard for a modern browser, but maybe I’m missing something. Is there anything I can do to improve?

(I know I can load each tab lazily, for faster initial loading, but I prefer slower initial load and fast switching between tabs)