When you use gridlines in your drawing, set the spacing to help your drawing be as precise as you need it to be.
To turn on gridlines, click View > Show > Grid.
On the View tab, click the Show dialog box launcher .
In the Ruler & Grid box, under Grid, in the Grid spacing lists, click Fixed. Enter the spacing distance that you want into the Minimum spacing boxes—the fixed grid won’t work without a number entered for Minimum Spacing.
For a variable grid, at Grid spacing, in the Horizontal and Vertical lists, click Fine, Normal, or Coarse.
Fine is the smallest grid spacing.
Coarse is the largest.
Variable or fixed grid?
Most of the templates in Visio use a variable grid by default. This means gridline spacing might change if you zoom the drawing view. For example, these gridlines are set at Normal, and when zoomed out, appear 5 feet apart.
However, when the view is zoomed in, they appear 1 foot apart.
For some drawings, it might help you to have a fixed grid, which means the grid shows the same spacing regardless of magnification. For example, with a fixed grid and Minimum spacing of 1 foot, the gridlines show 1-foot squares no matter how far in or out you zoom the drawing view.