Real easy to install and activate. Looks good feature wise but I haven't got time to test it now. 3yr licence is very nice too.

DupInOut Duplicate Finder 1.1.3.2 downloaded, installed, and registered without problems (Win 11).
Have only had time for a quick "test spin" thus far, but here are few notes nonetheless:

(TL:DR - Despite a couple of minor shortcomings, initial usage suggests that this is a Useful App that is Above Average for its type: I plan to use it over 2 other similar apps already installed on my system, and would Recommend it.)

1) DupInOut comes with a much better Help File (User Manual) than most similar products used to date.
Alas, this exists as a PDF - which is fine in & of itself - but the in-app "Help" button opens that same file in a web browser instead of offering the option of opening the local PDF. To be fair, this is typical behavior, and - again - the User Manual is actually Worth Reading!

2) Function of the Duplicate Search - tested on a Documents folder with 10 sub-folders - was adequately fast (for 1,500+ files and reporting 307 Duplicate Groups), and the resulting report (Review & Fix window) was typical for similar apps, but with the useful addition of the HASH for each file set which allowed grouping files with identical content but varying names. (Existence of such files was one reason this folder / sub was selected).

3) This window (Review & Fix) presents a number of seemingly-useful options, and - again - the User Manual is worth reading on this regard.

4) DupInOut includes a couple of additional utilities: Organize Files and Compare Folders, either of which could be useful.
I happen to be particularly fond of "Compare Folders" utilities, especially when it comes to Deleting (!) large number of "Duplicate Files," often finding it beneficial to Move any / all NON-Duplicates into a single folder. My standard apps for this purpose have been Compare Advance (from Bauerapps, the RightNote developer) or XYplorer (Cologne).
DupInOut presents a shortcoming with this function: It will not compare a Folder with one of its own Sub-Folders.
There is some logic behind that, HOWEVER DupInOut offers the Option to NOT Include Sub-Folders which should get around the problem of self-referral.

In the absence of some Glitch that might pop up in more extensive usage, I would put DupInOut on my (personal / FWIW / YMMV....) Recommended List.

This has become my go-to duplicate finder, I find it very manageable, and the results are easily selectable by group, such as "all but the first item in each group" - a keeper for me.

Thanks, GOTD and Vikas Medhekar of DupInOut.

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