.xlsx — Microsoft Excel Open XML Spreadsheet
Microsoft · 2007
XLSX is the default file format for Microsoft Excel spreadsheets since Office 2007.
Key Features
- Varies storage behavior for typical spreadsheet workflows
- Common MIME type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
- Recognizable file signature: 50 4B 03 04 (PK ZIP)
- Associated with Microsoft
Best For
- Structured calculations
- Business analysis
- Tabular collaboration
Less Ideal For
- Rich page-layout publishing
- Binary media delivery
- Executable packaging
Common Use Cases
- Calculations and formulas
- Reporting and dashboards
- Budgeting and tabular data
How to Open It
- On Windows, open the file with Microsoft Excel or LibreOffice Calc.
- On macOS, open the file with Microsoft Excel or Numbers.
- If the file does not open, confirm that the extension really matches .xlsx and that the download or transfer completed without corruption.
What is a .xlsx file?
XLSX is the default file format for Microsoft Excel spreadsheets since Office 2007. It stores data in cells organized into rows and columns, supporting formulas, charts, pivot tables, conditional formatting, and macros. The format is based on Open XML and uses ZIP compression, making files significantly smaller than the older .xls format. XLSX is the industry standard for business data analysis, financial modeling, and data management.
Programs That Open .xlsx Files
| Platform | Program | ||
|---|---|---|---|
| Windows | Microsoft Excel | Paid | Official |
| LibreOffice Calc | Free | ||
| Google Sheets | Free | ||
| macOS | Microsoft Excel | Paid | Official |
| Numbers | Free |
Common Problems with .xlsx Files
Frequently Asked Questions
.xlsx files can be opened with several programs. Microsoft Excel is one of the most popular choices.
Generally yes, .xlsx files are safe to open with appropriate software.
Yes, there are many online and offline tools available to convert .xlsx files. Check the conversion section above for specific methods.
Technical Details
Microsoft Excel Open XML Spreadsheet files use the application/vnd.openxmlformats-officedocument.spreadsheetml.sheet MIME type and were first introduced in 2007 by Microsoft. The file can be identified by its signature: 50 4B 03 04 (PK ZIP).