Up until OS X Yosemite, it was a pain the butt to batch-rename files.

You either had to do it manually, arduously replacing the file names one by one, download a specialized utility, use some Terminal command-line wizardry, or perhaps resort to a tool like Apple's Automator utility. Not any more, thanks to Yosemite. Here's how!

First of all, why would you want to batch-rename files? There are lots of reasons, actually. Maybe you've found a more efficient or more descriptive naming scheme than one you've developed previously. Or maybe you're working on a new project, and you'd like to differentiate the files you've already created from new ones. There are multitudes of reasons why it might be important to do so, but the bottom line is, before now, it's always been an uncomfortable process.

These days, thanks to Yosemite, it's much easier. Here are step-by-step instructions for how to do it.

To batch rename files

  1. Open a Finder window.
  2. Locate the files you want to rename.
  3. Shift-click to select multiple files, or lasso the ones you want to rename.
  4. Click on the Action button at the top of the Finder window. (Alternately, you can right-click or control-click the selected files to produce a contextual menu.)
  5. Select Rename [xx] items...
  6. Click the Rename button.

The Rename action is pretty versatile: You can either replace a segment of the filename with something else (using the Replace Text command), add text before or after the file name (using the Add Text command) or reformat the file names all together, indexing them with a number increment (using, predictably, the Format command.) Choose the method best suited for whatever you want to do.

Yosemite will take care of the rest. Easy peasy!

Select your files

Rename action

Format names

If you make a mistake, a quick command Z will undo the file name change.

Any questions? Let me know in the comments.