How to remove trailing spaces from filenames on Mac

What this does

A stray space right before a file’s extension is easy to miss and often comes from copying text out of an email or a document title. This rule trims exactly that: any space sitting right before the extension, so “Report .pdf” becomes “Report.pdf”, without touching spaces anywhere else in the name.

What you’ll build

A rule that matches every real file, then trims any trailing space right before its extension.

Open the rule editor

This walkthrough happens inside FilesAutomator itself, so install it from the Mac App Store first if you have not already, then open it. In its toolbar, choose Add, then New Automation Rule.

Name the rule and choose a folder

Name it something like “Remove trailing spaces from my filenames” and use Add Folder to choose the folder you want this applied to.

Build the condition

Add a single condition: Size is greater than 0, matching any real file.

FilesAutomator

Add the action steps

Step 1: Rename

Choose Add Step, then Rename. In “New name, built from the parts below”, use Add Part, then Find and Replace in Name. Turn on “Find is a pattern” and enter this pattern to find:

\s+$

Leave the replacement empty. Add Part again, choose Text, type a period, then Add Part once more and choose Extension.

FilesAutomator

Turn it on

Select Create Automation Rule, then switch the rule on. Every file that lands here now has that stray trailing space trimmed automatically.

A faster way

The template gallery inside FilesAutomator already has this rule ready to install, named Remove trailing spaces from filenames.