XLK File Extension

Excel Backup Format

File Type xlk
Developer Microsoft
Popularity
4.8 (35 votes)
Application Microsoft Excel
Category Backup Files

What is a XLK file?

The XLK file extension is linked to Excel Backup Format and belongs to the Backup Files category, which includes 395 files.

With the creation of the Excel Backup Format (XLK), Microsoft introduced file format along with 242 programs built for their use.

XLK file support extends to various operating systems, including Mac OS and Windows. You can open a XLK file using one of 2 programs, for example Microsoft Excel and Microsoft Office.

MIME types

application/vnd.ms-excel
application/excel
application/x-excel

Windows

Mac OS

How to open a XLK file?

The most common reason why a XLK file cannot be opened is the absence of required software. To fix this, select a compatible program from the list. Then visit the official developer website via the provided link, download the program, and install it on your system.

When it comes to opening and working with XLK files, Microsoft Excel and Microsoft Office are the top choices for users. If you want the most recent release of Microsoft Excel, head over to the Microsoft site and download the version designed to run on all platforms.

When you finish installing Microsoft Excel, the system will automatically launch XLK files with it.

Set Microsoft Excel to open XLK by default

Changing Default Programs in Windows

Start by right-clicking on your XLK file and selecting the "Open With" option. From there, click "Choose another app" to continue;
Find the Microsoft Excel application in the pop-up window and select it as your preferred program;
Select the "Always use this application" check box and click "OK" to save your selection as the default application for opening XLK files.

Change default apps on Mac

Right-click or use Control + Left-click on the desired XLK file to access the file’s context menu;
Select "Open in application" and click "Other";
At the bottom of the window, you will see the "Enable" menu. It is already set to the default option, "Recommended Programs";
Within this menu, select "All Programs" and then search for Microsoft Excel. Check the box next to "Always open in app" to make it the default program.

Easy XLK Troubleshooting

When facing challenges with XLK files, simple adjustments in your software can often solve the problem. Find helpful troubleshooting guidance below.

What Causes Microsoft Excel to Crash Frequently?

Microsoft Excel crashes can be attributed to outdated software. Make sure you have installed the latest updates for Microsoft products.

Restarting your computer is often an effective solution to resolve various common problems. Therefore, it is recommended to do so before making any changes to the software configuration.

How can I restore a damaged XLK file?

Use Microsoft Excel to open the damaged XLK file and select the "Repair" function from the menu. Then wait for the recovery process to complete, which allows you to automatically repair corrupted backup files.

What are the signs that my XLK file is damaged?

Common indications of damaged XLK backup files are:

Editing the archive in Microsoft Excel results in slow or unresponsive behavior;
File hangs or crashes in Microsoft Excel or other programs;
The file does not open or opens with errors;
Unexplained increase in XLK file size;
Working with the file triggers the display of error messages;

How to edit a XLK file?

To edit XLK files, it is essential to install software that supports not only viewing but also editing the backup files. Online XLK editors provide limited functionality compared to full-featured software for Excel Backup Format.

Best XLK editors in 2026

After analyzing the criteria, we have created a list of XLK editors available for use.

XLK Editor Software	Developer	Platforms	Overall Rating
Microsoft Excel	Microsoft	Windows, Mac OS, Apple iOS, Android	4.7 out of 5 (37 reviews)

Convert to and from XLK

If working with a XLK file is challenging, one solution is to convert it to formats like PDF, XLS, XLSX or other supported formats.

Keep in mind that converting a XLK file may introduce some limitations, but the original format can often be restored.