dupliFinder

dupliFinder is a Java-based application that identifies duplicate files in any specified folders and lets you delete the clones while preserving the original files. This way, you can clear up disk space and make room for new items.
The program compares files by calculating and attempting to match their MD5 checksums. It doesn't have configuration settings in regard to the search method applied.

No setup required, besides Java

It's wrapped in a single executable .jar file that can be copied to preferred directory on the disk or stored on a USB flash drive, and just double-clicked to run it on any PC.
Just keep in mind that you must have Java installed. It doesn't make any changes to your system registry. However, it auto-creates and updates a plain text document with log details. This can be disabled, though.

Straightforward GUI and options

The interface is user-friendly, made from a standard window with a Java appearance, where you can select the folder to scan. This task shouldn't take long, depending on its size, after which dupliFinder plays an audio player to let you know the job's over.

Remove duplicate files and calculate MD5 hashes

Once duplicates have been detected, you can check out the full path, original file name and MD5 hash of each item. The clones are automatically copied for deletion while the original files are left unchecked. Nevertheless, you can handpick the items you want to delete while sparing the rest.
The software utility is capable of deleting all selected files with one click, as well as of calculating the MD5 signature of any specified file, regardless of its format. Plus, you can disable sound effects and confirmation messages, hide the log and preview frames, or prevent the utility from creating log files.

Evaluation and conclusion

Unfortunately, it failed it its attempt to correctly identify several files as duplicates in our tests. These blind spots may be due to the fact that dupliFinder has compatibility issues with modern Windows versions, since it hasn't been updated for a long time. Otherwise, it carried out tasks swiftly while remaining light on system resources usage.