All diagrams can be zoomed in and out by using the Zoom control component or by keyboard shortcuts.
In the Masterplan diagram zooming changes the timespan that is shown, not the size of the entire diagram.
For all diagrams the "Zoom control component" is present in the top of toolarea between "Show in list"/"Saved Queries" and "Reset" buttons.
You can change the zoom by moving the slider or by pressing the "Zoom in"/"Zoom out" buttons. The current zoom value is always shown.
By keyboard shortcuts
All diagrams can be zoomed in and out using the following keyboard shortcuts:
Ctrl + Mouse wheel up, Keypad "+" — zoom in
Ctrl + Mouse wheel down, Keypad "-" — zoom out
Ctrl "0" — reset zoom (set to 100%)
Shift "Z" — zoom to fit in view
On a Macintosh the Command key is used as the modifier instead of the Control key.
On touch devices there is a default context menu that shows many commonly-used commands when you hold a finger down on the diagram.