qBittorrent official forums

It has become a standard in most software that
Ctrl + Wheel
act as a Zoom

useful for us Generation X that are ageing and beginning to lose sight.

https://en.wikipedia.org/wiki/Generation_X

And for what purpose you would like to zoom in qBittorrent, or where?

Where to zoom :
the list of the torrents, which is qBit's main part

Why to zoom :
because the font becomes too small when I leave my chair for my armchair.

And no I don't want to use Windows accessibility permanent features, they are not as versatile as Ctrl-Wheel.

Just use Ctrl-Wheel in your browser right and you will understand.