How to Open, Edit, & Convert XLK Files

Screenshot of several XLK files in Windows 10 that open with Excel
XLK Files.

A file with the XLK file extension is an Excel Backup file created in Microsoft Excel.

An XLK file is just a backup copy of the current XLS file that's being edited. Excel creates these files automatically in case something goes wrong with the Excel document. If, for example, the file is corrupted to the point that it can't be used any longer, the XLK file acts as a recovery file.

XLK files may also be created when exporting information from Microsoft Access into Microsoft Excel.

The BAK file format is another backup file used in Excel.

How to Open an XLK File

XLK files are most commonly opened using Microsoft Excel, but the free LibreOffice Calc program can open them too.

Note: If your XLK file doesn't open in either of these programs, be sure that you're not confusing it with a file that has a similar extension, like an XLX file, which has nothing at all to do with Excel. A number of other file types are used in Excel too, and they look very similar to XLK - XLB, XLL, and XLM are a few. Luckily, they all open in Excel with no problem so confusing the XLK file with one of those isn't a major issue.

Tip: Your XLK file is most likely an Excel Backup file, but you can instead use a free text editor to open the file if doing so doesn't work with Excel or some other spreadsheet program like Excel. With the file open in a text editor, even if it's not readable/usable, you'll be able to see if there's any text within it that might help you determine what program was used to build it.

If you have more than one program installed that supports XLK files, but the one that's set to open these files by default isn't the one you'd like, see our How to Change File Associations in Windows tutorial for help changing it.

How to Convert an XLK File

Opening an XLK file in Excel is just like opening an XLS file, which means you can use Excel's File > Save As menu to convert the file to any of Excel's other formats, like XLSX for example.

LibreOffice Calc supports some of the same formats as Excel. You can convert an XLK file in LibreOffice Calc by opening the file and then using the File > Save As... option. An XLK file can also be converted to PDF with Calc's File > Export... menu.

More Information on XLK Files

You can enable Excel backups on a per-document basis. When you go to save your XLS file to a specific folder, but before you actually save it, choose the Tools > General Options... option. Then just check the box next to Always create backup to force Excel to keep a backup of that specific document.

XLK files are really a version behind the current one that you've saved. If you save the file once and enable the backup, the XLS and XLK file will be saved together. But if you save it again, just the XLS file will reflect those changes. Save it once more and the XLK file will have the changes from the first and second save, but only the XLS file will have the most recently saved edits.

The way this works means that if you make a bunch of changes to your XLS file, save it, and then want to revert back to the previous save, you can just open the XLK file.

Don't let that all confuse you. For the most part, XLK files pop in and out of existence automatically and help to make sure you don't lose your data if something unfortunate happens to the open file.