xlsx

.xlsx — Microsoft Excel Open XML Spreadsheet

Microsoft · 2007

Developer

Microsoft

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

⚠️ Cannot open .xlsx file

Install one of the recommended programs listed above. For a free option, try the first free program in the list.

⚠️ .xlsx file is corrupted

Try re-downloading the file. If the file was transferred, ensure the transfer completed without errors.

Frequently Asked Questions

What program opens .xlsx files?▼

.xlsx files can be opened with several programs. Microsoft Excel is one of the most popular choices.

Is .xlsx a safe file format?▼

Generally yes, .xlsx files are safe to open with appropriate software.

Can I convert .xlsx to another format?▼

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).

Did You Know?

Microsoft Excel Open XML Spreadsheet was first released in 2007 by Microsoft

Security Information

.xlsx files are generally safe to open. However, always ensure your software is up to date to protect against potential vulnerabilities.