Does a plotly dash dashboard publish data online?

The documentation is indeed a bit confusing. Based on the four points below I would assume that no data is uploaded to the cloud.

• Your Flask app needs to be explicitly uploaded to the cloud, otherwise nothing will happen (https://plot.ly/python/create-online-dashboard/#upload-dashboard).

• In addition you don't need a Plotly account to create a Dash app, but you do need an account to upload a graph.

• Dash works locally without an internet connection, so no data can be uploaded

• There is no code indicating upload in the Dash code

I have recently been looking into this, as I shared your concern. What I found was that my data was being uploaded when I clicked the "Edit in Chart Studio" button. Using Dash, you can remove this button from your graphs with the following code:

import dash_core_components as dcc
dcc.Graph(
    id='test-div',
    config={'modeBarButtonsToRemove': ['sendDataToCloud']}
)