Automatically Batch Resize Images in Mac Using Automator

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Automator is an automation app that comes preinstalled with every Mac. It’s a simple utility where you create a workflow by specifying a set of instructions (called Actions) that the app will follow, one after the other. Automator can do everything from moving files or modifying files to complex things like launching scripts and interacting with apps. An overview of the Automator app is available here.

Today we’ll be focusing on a simple aspect of Automator. How to select photos from anywhere on your Mac and resize them to a set resolution. If you’re a web publisher or a photographer, you deal with image resizing constantly. More often than not, you’re resizing the image to one specific resolution – maybe a couple of them.

Wouldn’t it be great if you could just select the photos, right-click, select an option and have the photos resized and transported to a defined folder? Read on to find out how we can achieve that.

Setting up the Workflow

We’ll be using Services instead of folders so we can do this for images anywhere on the Mac.

To get started, open the Automator app from the Applications folder. You’ll see a window asking you to open an existing document or create a new one. Choose New Document. Now from the Choose Type document, select Service.

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You’ll now see the Library view listing apps, actions, and the workflow details.

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To specify that we’ll be working with images, select Image files from the dropdown menu beside Service receives selected.

Now search for an item that says Get selected Finder Items and drag it to the Workflow view. Search for Scale Images and do the same.

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Automator will now ask if you want to create a copy of the file before it is modified. If you want to keep the originals, select Add. In this example, we’re going with Don’t Add.

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The Scale Images section will show options for resizing images. Change the pixel size from 480 to anything you want. You can also use the Percentage metric.

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Select Save from the File menu and give the workflow a name.

Now, select any number of image files in question, right-click, hit Services, and select the workflow we just made. The images will be instantly edited and resized without you having to open any kind of extra tool.

Keeping the Original Files Safe

If you don’t want to mess with the original files, choose Add when Automator asks you if you want to copy finder items.

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This will add a Copy Finder Items menu in the workflow. Here you can select the folder where you want the resized image to be copied.

Keep Experimenting with Automator

Automator has many Actions and supports a majority of built-in (and some third party) apps. So go on exploring, drag in Actions, try to see if they work by pressing the Play button in the app. There’s a lot you can do here. If you come up with something interesting, share with us in the comments below.

Challenge Accepted: If you’re looking for a challenge, how about this – create a workflow that takes any new photo added to a designated folder, automatically resizes it, and deposits the copy to another folder. It’s easy – just dragging and dropping Actions like we did above. If you run into any problems, feel free to ask for help in the comments.

Last updated on 03 February, 2022

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