Reliable, if possible, Apple recommended File Duplicates Finder/Remover app

No. There are none. Most do damage to the system and/or application performance. Do not install or run any "cleaning", "optimizing", "speed-up", anti-virus or VPN apps on your Mac?

There are a couple of safe apps for detecting and identifying duplicate photos in a Photos library. They are:

PowerPhotos - $40  

PowerPhotos is the iPhoto Library Manager version for Photos and is very powerful. Although more expensive I would recommend it as it has more capabilities than the others like the capability to merge Photos libraries or copy photos, both original and edited versions, along with their metadata between libraries.

PhotoSweeper - $15 - Demo version available.

PhotoSweeper compares bitmaps and/or histograms so it can detect duplicate images even if they have different file sizes, file names, image sizes and capture dates.

Hey Paulo! On Catalina, there’s no official Apple-branded duplicate finder, but a few safe and reliable third-party options exist. Gemini 2 is well-known, user-friendly, and works smoothly on macOS 10.15—it’s even recognized by Mac communities for reliability. Another free option is dupeGuru, which is open-source and safe, though the interface is more basic. My advice: always double-check what’s being deleted and maybe back up important files before running a full scan—SSD space is precious, and you don’t want to accidentally remove something important.

pmonnerat wrote:

My purpose is to open space in my SSD

You may be laboring under a misconception. Duplicate files occupy no additional space on APFS formatted volumes.

If you need to increase available storage space read Free up storage space on Mac - Apple Support and Optimize storage space on your Mac - Apple Support.

queye wrote:

Hey Paulo! On Catalina, there’s no official Apple-branded duplicate finder, but a few safe and reliable third-party options exist. Gemini 2 is well-known, user-friendly, and works smoothly on macOS 10.15—it’s even recognized by Mac communities for reliability.

What AI gave you that nonsense? Gemini 2 is made by a company that is almost universally excoriated by anyone who knows anything about Macs.

<<. Duplicate files occupy no additional space on APFS formatted volumes. >>

John Galt is quite correct.

APFS makes clever use of pointers, ONLY, rather than making duplicate files.

pmonnerat wrote:

Hi Old Toad, unfortunately, or maybe more correctly, fortunately, you confirmed my feelings.

Thanks anyway Paulo