You might find four versions of the same pier photo in a trip folder. One is the original from your phone, one is that file with a new name, one was taken seconds later, and one is the crop you sent to friends. Applying one deletion rule to all four could cost you both a useful edit and a different moment.

Find exact duplicates

File names and dates are useful clues. Compare a SHA-256 checksum calculated from each complete file. A match is strong evidence that they are exact copies. Equal file sizes alone say much less. Even a small metadata change can alter the checksum.

Before keeping just one copy, look at the paths recorded in your editing catalogue. More than one project may rely on a particular location. Move a file, then check whether the album or project can still find it.

Open burst photos together

Sort the frames by capture time and review them in small groups. Open eyes in a portrait, the precise moment in a sports photo, or a distracting detail at the edge of a landscape can change your choice. Treat an app’s similarity suggestions as a review queue.

Give edited copies their own place

A full-size colour correction may represent hours of work. A small chat copy may be easy to recreate. Set aside the master and any edits worth keeping. When two names look alike, preview the files and check their dimensions and framing.

Rehearse on one folder

Move the candidates from a single trip into a temporary folder. Reopen the masters, album, and a few edits. Finish cleaning up once you can open the files you mean to keep from your backup too. Keeping originals, edits, and share copies separate during your next import saves you from repeating the work.

Compare two files that do not match

Suppose you have DSC_0421.JPG and pier-final.jpg in your archive. The thumbnails look identical, but one file may be 6,000 pixels wide while the other is only 1,600. Open both at 100% and look at the horizon, the corners and any fine details. A smaller file made for messaging cannot supply the detail of the master. On the other hand, a version you spent time retouching or framing differently may deserve to stay. Record its role as original, edit or share copy so you do not have to solve the same puzzle next month. Similar shots call for a separate decision. A travel album might need just one view of the pier, while two frames taken seconds apart at an event can show different people at their best. Review the frames as a group and note what each surviving file contributes. Try this on one folder before touching the whole archive.

Divide the cleanup into reversible steps

Write down the number of files in the folder and make a short list of what you intend to move. When working across different disks, copy the files first, open them at the destination, and decide what to remove only afterwards. If two exact copies have different dates, preserving the path used by your editing catalogue can matter more than keeping the newest modification date. Move candidates to a temporary folder and continue with your usual work. An album, export or new edit may expose a missing reference. Use the original path in your notes to put that file back. If a folder synchronises between devices, account for how moving a file will affect the other copies. Choose a review period during which you can still reach your backup. Set uncertain pairs aside instead of settling them while tired. At your next review, the names and locations should tell you what each file is for. Once a duplicate is gone, check that the archive and the separate backup still contain the file you chose to keep.