How to Batch Rename Files on Mac
You downloaded 200 photos named IMG_4392.jpg through IMG_4591.jpg. You need them named 001.jpg, 002.jpg, etc. Or maybe you just want every filename lowercase. Doing it one by one is not an option.
Here are three ways to batch rename files on macOS — from built-in to powerful.
Option 1: Finder Built-In Rename
Free, no setup, but very limited.
- 1 Select files in Finder
- 2 Right-click > Rename...
- 3 Choose "Replace Text", "Add Text", or "Format"
- ✗ No lowercase conversion
- ✗ No space-to-underscore replacement
- ✗ No custom numbering format (001, 002...)
- ✗ Limited to simple find-and-replace patterns
Result: Works for basic text replacement. Anything else? You're stuck.
Option 2: The Sane Way (SaneClick)
Right-click rename scripts, ready to go.
- ✓ Rename with Sequence: Files become 001, 002, 003...
- ✓ Lowercase Filenames: One click, all files lowercased
- ✓ Replace Spaces: Spaces become underscores instantly
- ✓ Batch support: Select any number of files
- ✓ Safe: Uses
mv -n— never overwrites existing files
What About Terminal?
You can rename files in Terminal with a for loop:
for f in *.jpg; do mv "$f" "${f// /_}"; done
This works, but one typo can rename or overwrite files permanently. There's no undo in Terminal. SaneClick's rename scripts use mv -n (no-clobber) so existing files are never overwritten, and you get a notification when the rename is done.
SaneClick's Rename Scripts
Rename with Sequence numbers your files as 001.jpg, 002.jpg, 003.jpg — preserving the original extension. Lowercase Filenames converts My Photo.PNG to my photo.png. Replace Spaces with Underscores turns my vacation photo.jpg into my_vacation_photo.jpg. All three work on any number of selected files.
Conclusion
Finder's built-in rename handles simple cases. Terminal is powerful but risky. If you want safe, fast batch renaming from a right-click menu — without memorizing shell commands — SaneClick has you covered.