What is a TSR file?
A .TSR file is primarily a Time-Stamp Protocol Response token. These files follow the IETF RFC 3161 standard. Software uses them to verify exactly when a digital signature or file was created. When a computer requests a timestamp from a secure server, the server sends back a .TSR file to confirm the time.
Because the .TSR extension is very short, many different programs use it. A .TSR file can also be a surveying data file used by Topcon Corporation, a shared Object Repository for testing software like Micro Focus UFT, or a Tracker Status Report used by Subsite Electronics. Gamers might also see .TSR files as save data exported from the TerraSavr web editor for the game Terraria.
How to open TSR files?
Because a .TSR file has multiple possible meanings, viewer.online/tsr analyzes .TSR files to identify their exact format and creator software, shows which programs can open the file, and usually previews it.
If your file is a security token, you can inspect it using command-line tools like SignTool.exe. If it is survey data, you need Topcon Link. If you do not know which software created your file, you should not guess or install random software. You can simply inspect it online first.
Best practices and troubleshooting
Never modify a .TSR timestamp file in a text editor. These files are cryptographically signed. Any change will break the digital signature and invalidate the timestamp permanently.
Summary
Because .TSR files use the known certificate?? format, viewer.online/tsr can safely open and display them online, eliminating compatibility problems.