XLS File Extension

What is XLS file?

File with .XLS extension contains spreadsheet document created with Microsoft Excel. XLS is a binary file that uses either MS-XLS BIFF8 or BIFF5 standard. Binary XLS file format was used by Microsoft Excel versions 97 to 2003 and older Excel 5.0/95. Up-to-date XLS specification document (which is more than 1000 pages long) can be downloaded from Microsoft website. XLS has been replaced by newer XLSX format, which is an XML Spreadsheet-based text format that uses UTF-8 encoding. XLS BIFF8 files are still commonly used and supported by many spreadsheet tools. XLS file structures is comprised of such elements as:

• Tables storing text or numbers,
• Formulas,
• Links to external resources,,
• Charts,
• Images

XLS spreadsheet file stores various types of data in cells organized in a table with rows and columns. Each cell has a unique address. Spreadsheet documents can be used for performing calculations, creating documentations, for organizing and visualizing data, etc. Users can format text, create tables, charts, or formulas based on data stored in such file. Depending on the program, XLS files can be exported into other formats.

Programs which support XLS file extension

The list that follows enumerates programs compatible with XLS files, divided into 4 categories based on operating system on which they are available. XLS files can be encountered on all system platforms, including mobile, yet there is no guarantee each will properly support such files.

Updated: 08/31/2023

How to open file with XLS extension?

Being unable to open files with XLS extension can be have various origins. On the bright side, the most encountered issues pertaining to Excel Spreadsheet files aren’t complex. In most cases they can be addressed swiftly and effectively without assistance from a specialist. The following is a list of guidelines that will help you identify and solve file-related problems.

Step 1. Install Microsoft Excel software

The main and most frequent cause precluding users form opening XLS files is that no program that can handle XLS files is installed on user’s system. This one is an easy one. Select Microsoft Excel or one of the recommended programs (for example, Microsoft Works, WordPerfect Office, Microsoft Excel Viewer) and download it from appropriate source and install on your system. The full list of programs grouped by operating systems can be found above. One of the most risk-free method of downloading software is using links provided by official distributors. Visit Microsoft Excel website and download the installer.

Step 2. Check the version of Microsoft Excel and update if needed

If the problems with opening XLS files still occur even after installing Microsoft Excel, it is possible that you have an outdated version of the software. Check the developer’s website whether a newer version of Microsoft Excel is available. It may also happen that software creators by updating their applications add compatibility with other, newer file formats. The reason that Microsoft Excel cannot handle files with XLS may be that the software is outdated. All of the file formats that were handled just fine by the previous versions of given program should be also possible to open using Microsoft Excel.

Step 3. Set the default application to open XLS files to Microsoft Excel

If the issue has not been solved in the previous step, you should associate XLS files with latest version of Microsoft Excel you have installed on your device. The process of associating file formats with default application may differ in details depending on platform, but the basic procedure is very similar.

Change the default application in Windows

• Clicking the XLS with right mouse button will bring a menu from which you should select the Open with option
• Click Choose another app and then select More apps option
• Finally select Look for another app on this PC, point to the folder where Microsoft Excel is installed, check the Always use this app to open XLS files box and conform your selection by clicking OK button

Change the default application in Mac OS

• From the drop-down menu, accessed by clicking the file with XLS extension, select Information
• Proceed to the Open with section. If its closed, click the title to access available options
• Select Microsoft Excel and click Change for all...
• Finally, a This change will be applied to all files with XLS extension message should pop-up. Click Continue button in order to confirm your choice.

Step 4. Check the XLS for errors

Should the problem still occur after following steps 1-3, check if the XLS file is valid. Being unable to access the file can be related to various issues.

1. Check the XLS file for viruses or malware

If the XLS is indeed infected, it is possible that the malware is blocking it from opening. Scan the XLS file as well as your computer for malware or viruses. If the scanner detected that the XLS file is unsafe, proceed as instructed by the antivirus program to neutralize the threat.

2. Ensure the file with XLS extension is complete and error-free

If you obtained the problematic XLS file from a third party, ask them to supply you with another copy. During the copy process of the file errors may occurred rendering the file incomplete or corrupted. This could be the source of encountered problems with the file. If the XLS file has been downloaded from the internet only partially, try to redownload it.

3. Ensure that you have appropriate access rights

There is a possibility that the file in question can only be accessed by users with sufficient system privileges. Log out of your current account and log in to an account with sufficient access privileges. Then open the Excel Spreadsheet file.

4. Check whether your system can handle Microsoft Excel

If the system is under havy load, it may not be able to handle the program that you use to open files with XLS extension. In this case close the other applications.

5. Check if you have the latest updates to the operating system and drivers

Up-to-date system and drivers not only makes your computer more secure, but also may solve problems with Excel Spreadsheet file. Outdated drivers or software may have caused the inability to use a peripheral device needed to handle XLS files.

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