What is a BK1 file?
A .BK1 file is a backup file created by several different software programs. The most common type is an Autodesk Backup File. Software like Autodesk ReCap and Autodesk AutoCAD create these files to protect project data. In ReCap, a .BK1 file is a compressed archive that uses the standard ZIP format.
Other programs also use the .BK1 extension for backups. These include payroll data from Moneysoft Payroll Manager, structural equation models from IBM SPSS Amos, data models from erwin Data Modeler, and risk analysis files from APIS IQ-Software. Sometimes, it acts as a Windows Indexing Service file.
How to open BK1 files?
To open a .BK1 file on your computer, you usually need the original software that created it. For example, if it is a ReCap project backup, you must use Autodesk ReCap. If it is a drawing backup, you need Autodesk AutoCAD or BricsCAD.
Because the .BK1 extension has multiple possible meanings, you might experience errors if you guess the wrong software.
Best practices and troubleshooting
If you know the origin of your .BK1 file, you can often restore it by removing the .BK1 extension and replacing it with the original extension. For AutoCAD, you might rename it to .DWG. For ReCap, you might rename it to .RCP. Always make a copy of the file before you change the extension.
If you do not know the origin of the file, do not rename it immediately. You must inspect the file contents to find its true format.
Software and tools
Summary
viewer.online/bk1 analyzes .BK1 files to identify their exact format and creator software, shows which programs can open the file, and usually previews it. Because a .BK1 file can belong to many different applications, viewer.online/bk1 is the best way to identify the actual format of your file. Because .BK1 files often use the known ZIP format, viewer.online/bk1 can safely open and display them online, eliminating compatibility problems.