Batch File Rename Preview

Preview Is the Feature — Use It Every Time

Bulk renames are the classic one-click disaster: an off-by-one numbering scheme or a pattern that matches the extension turns 200 files into a recovery project. The preview list exists so that you verify the oldest and newest file alphabetically, plus one in the middle, before committing. Keep extensions out of the pattern, and when numbering, decide whether the first item is 0 or 1 before the rename — both conventions exist and mixing them across folders is why photo sets end up misordered.

Previewing a Rename Safely

Mass renaming is easy to get wrong, and an undo is often not available. A preview shows exactly what each name becomes before you touch a single file, so you can catch duplicates and mistakes early. Check that numbering is padded (001, 002) so files sort correctly, because photo10 sorts before photo2 without padding.

Avoid characters that some systems reject, such as colons, slashes, question marks and trailing dots, and keep names unique within a folder. Apply the pattern on a copy of the folder first if the files matter, and keep the original names in a list in case you need to reverse the change.