WhatsOpen for Mac

Quick summary

WhatsOpen is a free utility for macOS that lists files and folders currently in use. It reveals which applications and background processes are accessing items on your drive, giving you a clear view of active resources. The app keeps its interface minimal so you can scan open files and understand who’s using them without a steep learning curve.

Typical users and benefits

This tool is useful for anyone who needs to troubleshoot locked files, manage system responsiveness, or simply see what’s holding onto disk resources. Because it runs with a small footprint, it’s a good fit for users on older Macs or those who prefer lightweight utilities.

Key capabilities

• Close or quit applications straight from the app’s window to free up a file or resource.
• Identify which processes or apps are currently keeping particular files open.
• Run with minimal impact on memory and CPU, suitable for constrained systems.
• Navigate a simple, uncluttered interface that makes locating open items quick.

Suggested alternative

If you want another free option to explore, consider CheatSheet — a no-cost app that provides quick access to shortcut and key-command references and can complement system-inspection tools.