You can change the date & time format in Google Sheets & Excel Online using this guide. Use different date & time formats in spreadsheets.

Open the Excel 2010 file that you want to make format changes to. Select the top-left cell in the range of cells that you want to change to the accounting format.

When you type a seven-or-ten-digit phone number into an Excel cell that uses the phone number format, Excel will automatically change the way the number looks so that it appears as a phone number ...

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.

You can add a strikethrough in Microsoft Excel using the software's Font Settings button or a keyboard shortcut.

You may have used Excel for years without delving into Styles (or stylesheets). We’re going to cover Cell Styles, and Smart Art, Drawing, Graphics, Picture, and Chart Tools.