.XLSX File Extension
Full form: Excel Open XML Spreadsheet
What is a .xlsx file?
The Microsoft Excel workbook format that holds rows, columns, formulas, charts and multiple sheets. Files that end with .xlsx belong to the document family of file types, so your computer links them with a suitable program automatically.
Where is .xlsx used?
Accounts, marks lists, budgets, data analysis and attendance sheets. Because the format is so common, almost every modern device and software understands it.
Examples of .xlsx file names
marks.xlsx, budget.xlsx
How to open a .xlsx file
You can open it with: Microsoft Excel, LibreOffice Calc, Google Sheets. If it does not open, check that the file is not damaged and that you have downloaded it fully; also confirm that the extension was not renamed by mistake.
Quick tips
Never rename a file just to change its extension, because that does not convert the data inside. Use a proper converter or the Save As / Export option. Keep a backup copy of important document files before editing them.