Open an Excel spreadsheet Select the cell or cells Click on the Borders button Select an option from the Border menu Change the color. To begin, open the Excel spreadsheet. The next step is to ...

To change Gridline color in Excel, use Excel Options, apply a custom-colored border to the cells, or apply a custom line color. Full details here.

The default active cell format in Microsoft Excel isn't all that easy to see, but you can use this easy-to-implement code solution to change that.