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

Like Microsoft Excel, you can change the formatting of date and time in Google Sheets as well. For that, select the cell where the date/time is visible, go to Format > Number, and select ...

If you have to work with a date stamp in Microsoft Excel that includes date and time, you can use these simple expressions to extract both components, making them easier to work with.