While it’s not quite as easy as opening .docx files in Pages for Mac, it’s not an overly complicated process either. Here's how to open .xlsx spreadsheet files on Mac, iPhone or iPad.

If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

If your Excel files are opening in Notepad on Windows PC, here's how you can reset the settings to make .xls, .xlsx, etc files open in Excel.

Designed for use with Office 2000, XP, and 2003, the downloadable add-on allows you to open, edit, and save the newer file formats, seamlessly converting the files on the fly and in the background.