Understanding The Difference Between XLS And XLSX In Tabular Form

Understanding The Difference Between XLS  And XLSX In Tabular Form

Basis of Comparison	XLS	XLSX
Version	XLS is the older version of Microsoft Excel.	XLSX  is the latest version of Microsoft  Excel
Main Difference	XLS is the default file format for the 2003 version of Excel	XLSX is the file format for versions since 2007.
Storage of Information	XLS is based on BIFF (Binary Interchange File Format) and as such, information is directly stored to a binary format.	XLSX is based on the Office Open XML format, a file format that was derived from XML. The information in an XLSX file is stored in a text file that uses XML to define all its parameters.
Speed performance	XLS version of the file is faster especially on files that require the use of complex formula for a large set of data.	XLSX version of the file is slower especially on files that require use of complex formula for a large set of data.
Readability	XLS is readable by all Microsoft Excel versions.	XLSX is only readable by Microsoft Excel versions 2007 and onwards.
Capability	XLS is capable of holding the spreadsheets either containing Macros or not.	XLSX is not capable to support Macros.
Based On	XLS is a proprietary binary format.	XLSX is based on office open XML format.

Summary - What is the main difference between XLS and XLSX versions of Microsoft Excel?

XLSX and XLS files are Microsoft Excel spreadsheets commonly used to store financial data and to create mathematical models. These files store data in worksheets that contain cells arranged as a grid of rows and columns. Excel spreadsheets may also contain charts, mathematical functions and various kinds of cell formatting. Spreadsheets are often used in business contexts to store financial data and to perfom mathematical computations.

The main difference between XLS and XLSX is that XLS files use a proprietary binary format whereas, XLSX use a newer file format known as Open XML. Another difference is that the XLS extension is used by Microsoft Excel 2003 and earlier whereas the XLSX extension is used by Microsoft Excel 2007 and later.