Indeed - you can easily zoom in and out your Kanban board using the built-in zoom, available in Settings - Board Background.
Board Settings are only accessible to board owners and account admins/owners.
You can also use the build-in browser zoom.Just press the CTRL and + - keys (or CTRL and mouse scroll) to zoom in and out. To go back to the default view use: CTRL and 0.
Using the browser zoom will only rescale your own view of the board. Using the Kanban Tool built-in zoom will resize the board for all its users.
For more information, please read and article on making the Kanban board view larger.