Which duplicate files and folders finders exist for Windows? [closed]

I need a free duplicate file finder/remover app, with ability to find duplicate files/folders by name and/or by size and to remove one of duplicates.

There was this Duplicate File Finder available for some time but now its only on secondary sites, like this Softpedia reference.

The Wareseeker site shows the correct reference http://dff.nazrashid.com/ which is no longer around. I would be careful fetching executables from such sites though.

It can do search for duplicates within multiple directory trees based on,

• contents (i think it does a md5 match)
• size
• name
• name and size
• contents and name

And, it lets you filter your search by a minimum and maximum files size (speeds up things when you know the bounds).

A very thoughtful piece of software. Don't know if there is something as fast and featured for free around these days.

The comments refer to a similar Sourceforge tool called Doubles

I have tried literally dozens of duplicate file finders (I still have the installers/ZIP files for about 20 of them sitting around). I used CloneMaster 2.19 for a time because it was the best one I could find, though even that wans’t perfect (I wanted one that could also detect duplicate MP3s by audio content, ignoring the tags). All of them had problems that frustrated me enough that I decided to write my own and laid out a list of the features I demand of a DFF.

And then I found AllDup. It is the first and only one that actually made me abandon a project (technically mine isn’t completely abandoned, it’s just no longer being worked on since I don’t need to write it anymore because AllDup does everything I want of it). Anyway, AllDup searches for duplicate files, but unlike the others, it uses a lot of the tricks and techniques that I was going to use in my own DFF. As such, it is very fast: it can for example scan >250,000 of sizes from 1B-5GB in ~30mins (I have done it on my system several times).

Another great (and for some reason rare) feature of AllDup is as I mentioned that it can scan for duplicate MP3s by their actually audio data while ignoring tags, so two MP3s that are the same but have differing tags (very common when downloading) will be detected as duplicates. (It could even detect when I ripped two identical songs from two different CDs—with different tags of course.) Of course it can detect dupes based on other factors besides byte-for-byte content, like filenames, dates, etc.

Other great features of AllDup include the ability to filter (include or exclude) based on filename and/or folder name and/or filesize. The results screen is also very versatile with options to select files based on date, path, name, this, that, the other… It also has variety in what to do with detected duplicates

Michael Thummerer is also very receptive. I have reported bugs and suggested features to him several times which he addressed extremely quickly (to the point that he told me to download and try out a beta with the updates in the very next emails the same day).

Oh and it’s free.

HTH

Duplicate Cleaner is very fast and it has extensive result set filtering possibilities.

Clonespy http://www.clonespy.com

I find this very helpful and more useful than doublekiller. A particularly nice feature is the "Pools" feature, where you can compare one group of directories with another group of directories while ignoring duplicates within the groups.

For example, my partner likes to keep duplicate image files while working with images. I want to see if I have any copies of those files in my directories.

Pool 1 - Partner Home Directory Pool 2 - My Home Directory.

The only duplicates found are if a file is present both in my directories and my partner's directories. The files only duplicated in my partner's directories are ignored.

I have the following batch file lying around for some time:

@ECHO OFF
REM TODO: Help when run with /? and switch for recursion
REM Furthermore check whether we might have enough files to hit the envvar length limit
REM and switch strategies accordingly (slower but finds all dupes then)
SETLOCAL ENABLEEXTENSIONS ENABLEDELAYEDEXPANSION
REM This method speeds up comparison but suffers from long file lists
REM as environment variables have a length limit
SET FILELIST=
FOR %1 %%i IN (*) DO (
    FOR %%j IN (!FILELIST!) DO (
        IF %%~zi EQU %%~zj (
            fc /b "%%~i" "%%~j">NUL && echo "%%~i" = "%%~j"
        )
    )
    SET FILELIST=!FILELIST! "%%~i"
)
ENDLOCAL
GOTO :EOF

You can run it with /r as argument to run recursively through the directory tree.