The object in Xcode: UIToolbar is locked when using the Interface Builder at 44 px tall. You can easily change this programmably by using setFrame
[myToolbar setFrame:CGRectMake(0,50,320,30)];
However you are able to do this in the Interface Builder as well by creating a constraints for the UIToolbar. Select the toolbar element and choose Editor > Pin > Height. You can now select the constraint and change the height to e.g. 30 px.