xlsb

.xlsb — Excel Binary Workbook

Microsoft · 2007

Developer

Microsoft

What is a .xlsb file?

The .xlsb file format is a binary representation of Microsoft Excel workbooks, designed for faster performance and smaller file sizes compared to XML-based formats. It stores all the data and formatting information in a compact binary structure. This format is particularly useful for very large spreadsheets or those containing complex macros.

Programs That Open .xlsb Files

Platform	Program
Windows	Microsoft Excel	Paid	Official
	LibreOffice Calc	Free
macOS	Microsoft Excel	Paid	Official
	LibreOffice Calc	Free

Common Problems with .xlsb Files

⚠️ Cannot open .xlsb file in older Excel versions.

Save the file as a compatible format like .xlsx or .xls from a newer version of Excel, or use compatible software that supports .xlsb.

⚠️ .xlsb files are not compatible with all spreadsheet software.

Try opening the file in Microsoft Excel, or convert it to a more universal format like .xlsx if compatibility issues persist with other applications.

⚠️ Large .xlsb files may still be slow to load.

Optimize the spreadsheet by removing unused cells, reducing formatting complexity, and disabling unnecessary macros, or consider splitting the data into multiple files.

Frequently Asked Questions

What is the main advantage of the .xlsb format?▼

The primary advantage of the .xlsb format is its speed; it loads and saves much faster than the XML-based .xlsx format, especially for large files. It also typically results in smaller file sizes.

Can I open .xlsb files with Google Sheets or Apple Numbers?▼

Direct support for .xlsb files in Google Sheets and Apple Numbers can be limited. While some import functionality might exist, it's generally recommended to use Microsoft Excel or compatible software for the best results, or convert the file to a more compatible format like .xlsx.

Is the .xlsb format safe to use?▼

Like any file format, .xlsb can potentially contain malicious code if it originates from an untrusted source. Always ensure you are using up-to-date antivirus software and only open .xlsb files from reputable sources, especially if they contain macros.

Technical Details

The .xlsb format stores data in a binary stream rather than XML. It uses the OLE Compound File Binary Format, which allows for multiple files to be embedded within a single file. Its header typically starts with the signature `D0 CF 11 E0 A1 B1 1A E1`.

Did You Know?

The .xlsb format was introduced with Excel 2007 as part of the Office Open XML (OOXML) file format family, though it is a binary format, not XML-based.

Security Information

While .xlsb is a binary format and less prone to direct XML injection attacks, it can still contain macros which may carry malicious code. Always exercise caution when opening .xlsb files from unknown or untrusted sources.