The call to MainLoop will pack the window and calculate the size of the widgets.
Create a Button to call a sub, it will give you the correct height.

The Tk-Debugger has it's own MainLoop, well sort of. So height will be printed correctly.

Update:
Putting a $main->update() before the print will work.

In reply to Re: Height of a label widget in Tk by busunsl
in thread Height of a label widget in Tk by Jouke

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