In Microsoft Project, the Gantt chart is the central tool you need to manage your project. Taking full advantage of the visual tools the chart offers can be a very powerful step in communicating Microsoft Project – changing text size on Gantt Chart. Posted on November 15, 2017 by jdonbavand. If you have text on top of Gantt bars, it can sometimes take up a lot of space and make each row quite deep. Microsoft Project 2016 and tagged Gantt Chart text size, Microsoft Project.