macOS has had a batch renamer built into the right-click menu since 2014, and most people have never opened it. It is genuinely good, it is free, and it will handle a large share of what you need. It also has one hard limit that is worth understanding before you start, because it decides whether the job takes two minutes or an afternoon.
The renamer already on your Mac
No download, no licence, and it handles hundreds of files without complaining.
- Select the files in Finder. Command-A for all of them, or click and shift-click for a range.
- Right click any of the selected files and choose Rename, which will say Rename N Items.
- Pick one of the three modes from the dropdown at the top left of the window.
- Fill in the fields. The example line at the bottom shows you the result before you commit.
- Click Rename.
Replace Text
Find something in the existing names and swap it for something else. This is the one you will use most: stripping a prefix everyone added, fixing a misspelling across a folder, turning underscores into spaces.
Add Text
Put a fixed piece of text before or after every name. Useful for tagging a batch with a client, a date or a version, as long as the text is the same for all of them.
Format
Throw the old names away and build new ones from a base name plus a counter or the date. This is the one that renames Photo 4837 to Live Set 01, and the one most likely to lose information you wanted to keep.
Where Finder runs out
Every one of those three modes has the same blind spot. Finder only knows the name the file already has, its position in the selection, and its date. It has never looked inside the file.
That is fine when the existing names are consistent and wrong in the same way. Strip the same prefix off 300 files and you are done in seconds. It falls apart the moment the names are inconsistent, because a rule that fixes half the folder mangles the other half.
And it cannot help at all when the information you want in the name is not in the name yet. If a file is called Track 04 and you want it called by its artist and title, Finder has nowhere to get that from. The artist and title are inside the file, in its tags. Finder does not read tags.
| Approach | Old name | Counter or date | What is inside the file |
|---|---|---|---|
| Finder Rename Items | yes | yes | no |
| Pattern based renamers | yes | yes | no |
| Reading the file's own tags | optional | yes | yes |
The Shortcuts and Automator route
macOS can automate renaming without any third party app. Shortcuts has a Rename File action, and Automator has a Rename Finder Items action, both of which can be saved as a Quick Action so they appear in the right-click menu.
This is worth the setup if you do the exact same rename repeatedly, for example every time you offload a card or receive a delivery. What it does not give you is any more intelligence about the files. The actions are the same three ideas Finder offers, just saved for reuse.
Renaming from what is inside the file
This is the category most people are actually looking for when Finder disappoints them.
Plenty of files already carry the information you want. Audio files carry tags: artist, title, album, BPM, key. Photos carry the camera, the lens and the moment they were taken. A renamer that reads those can build a name that is correct regardless of what the file was called before, which means it does not matter that your folder is inconsistent.
It also flips the safety story. A pattern rename gets less reliable as the folder gets messier. A rename that reads the file does not care how messy the folder is, because it is not using the old name as its input.
Rules that keep a batch safe
These apply whatever tool you land on, and they are the difference between a rename you can trust and one you have to unpick.
- Preview before you commit. If a tool cannot show you the old and new names side by side, that is the feature to go find somewhere else.
- Watch for collisions. Two files that end up with the same name is the one failure that actually loses data. Good tools number the duplicate instead of overwriting.
- Decide about extensions before you start. Renaming a file to something without its extension will confuse macOS about what it is.
- Be careful with slashes and colons. They have meaning in file paths and behave unpredictably inside names.
- Work on a copy the first time you run a new rule across a large folder. Once you trust the rule, you can stop doing this.
If the files are music
Music is where this gets both worse and easier. Worse because a library collects names from every source it ever touched: promos, purchases, rips, things a friend sent. Easier because almost every audio file already carries tags, so the correct name is sitting inside the file waiting to be used.
RenameBrooo does that job. It batch renames thousands of audio files at once, reads and fixes the ID3 tags, and can build the filename out of artist, title, version, BPM and key rather than out of whatever the file happened to be called. Every change is shown in a side by side preview before anything is applied, and the audio itself is never touched.