Decide which job you have
- Make the format consistent. Add the same prefix, replace a word, number files in order. The names already carry information; they are just untidy.
- Name by content. The file is called scan0042.pdf or "download (3).pdf" and the name says nothing, so something must read the file to learn what it is.
Option 1: Finder's built-in rename
Select several files, Control-click one, and choose Rename. The window offers three operations: replace text, add text, or give the whole batch a new format (a custom name plus an index or a date). Press ⌘Z if you get it wrong.
The limit is clear: it only touches the characters of the name and never opens the file. Information that is not in the name cannot appear from nowhere.
Option 2: Automator or Shortcuts
Automator has a "Rename Finder Items" action that you can chain into a workflow. Its options are of the same kind: add a date or time, add text, change case, make sequential, replace text. It automates repeated batch renames, but it is still format rules. Naming by content means adding text recognition and your own scripting, which is costly to maintain.
Option 3: Rule-based tools such as Hazel
Hazel watches folders you choose and runs actions when your conditions match. Its site lists conditions such as name, date, type and the site a file came from, and actions such as moving, renaming, tagging and uploading. Once a rule is written it runs reliably; the catch is that it only covers cases you thought of. What a PDF says is not something a rule sees. For Hazel against Filewise, see this comparison.
Option 4: A local tool that reads content, such as Filewise
Filewise opens the file itself: it reads the text layer of a PDF, runs Apple Vision recognition on scans and screenshots in Chinese and English, and assembles the findings into a name.
- Download and install. On first launch grant Full Disk Access and let it download the local AI model (about 2 GB, once; Macs with Apple Intelligence can use the system model).
- Pick a batch of PDFs, or let it watch your Downloads folder.
- Read the plan: each row is "old name to new name" with the reason. Drop or edit any row you do not like.
- Approve it. Every step lands in the undo log and can be reverted in one click.
The naming structure is adjustable in Settings: date first, last or none; year-month-day, compact, or month only; and four separators (underscore, hyphen, space, dot).
When it misreads
A local model does not understand as much as the strongest cloud models. Blurry scans, unusual layouts and handwriting may produce incomplete results. When confidence is too low Filewise keeps the original name and queues the file for you instead of guessing, so try a batch of unimportant files first.
Which to choose
| Your situation | Use |
|---|---|
| The names carry information and you only want a common prefix or numbering | Finder's built-in rename |
| A fixed pattern you want to run automatically | Automator, or a rule tool like Hazel |
| Names say nothing and you need the content to know what a file is | A tool that reads content, such as Filewise |
The Finder steps follow Apple's "Rename files, folders, and disks" guide, checked 2026-10-13.
FAQ
Can Finder rename PDFs based on their content?
No. Finder batch rename only changes the characters of the name: replace text, add text or apply a format. It does not open files to read them.
Will Filewise overwrite a file with the same name?
No. If the target already has a file with that name, it does not overwrite; it appends a number to the new name so both files stay.
Does renaming by content need the internet?
No. Reading and naming run offline on your Mac. The first launch downloads the local model once, and Macs with Apple Intelligence can use the system model with no download.
Sources and check dates
- Finder batch rename: Apple, "Rename files, folders, and disks", checked 2026-10-13.
- Hazel conditions and actions: noodlesoft.com, checked 2026-10-13.
