19 May 2012Blog

Batch image resize on a Mac

by Monique

Batch image resizing with Preview.appLearn how to batch image resize on a mac. As you can imagine, managing a real estate website we process a LOT of images. Now, there are plenty of paid options out there in the Mac App Store, and we have experimented with most, but we generally end-up using good old Preview.app. Preview.app is the native image editor in OS X and it comes FREE with every Mac.

Resize bulk images in Preview.app

  1. Select all the images you want resized in the Finder and open them within Preview.app
  2. From Preview, select the images that you want to batch resize from the drawer (Command+A will select them all)
  3. Now, go to the menu labeled Tools, and then Adjust Size
  4. Enter a value for what you want the new width and height to be
  5. Next, navigate to the File menu and click Save All
  6. All the images you selected are now resized!

Not only can you resize images, you can also change the resolution, rotate and flip many images in one go. The only thing Preview.app doesn’t seem to allow is bulk changes to JPEG compression. Luckily we have a WordPress plugin for that.

Remember when saving images for the web, always use 72 dpi!