However, if you are looking for the on a Mac that offers the same ease of use, or if you are looking for the official Microsoft tool that replaced it, you have two main options:

A robust media browser and viewer that supports batch conversion and is very similar in layout to legacy Windows image managers.

A high-performance photo and video viewer designed specifically for macOS. How to use "Picture Manager" features on Mac To Compress Images : Open the image in File > Export

Ignore any website that says “Download Microsoft Office Picture Manager for Mac free new full version.” If the file ends in .dmg and is under 50MB, it is likely adware.

Microsoft Office Picture Manager was a basic photo management and editing tool included in older versions of Microsoft Office for Windows (Office 2003, 2007, 2010). It was never released for macOS . Microsoft discontinued it entirely after Office 2010 on Windows, and it has never been part of Office for Mac.