In macOS, you can easily convert the format of images using a quick action in the Finder or you can achieve the same through the Preview app, but if your daily workflow requires you to convert repeatedly images – to upload to a blog, for example – then using a folder action can be a much faster way to get the job done.

In this article, we’ll show you how to use the macOS Automator app to create a very simple Folder Action that will automatically convert images dropped into a specific folder, without you having to manually apply a Quick Action or open an app from image retouch. Keep reading to find out how it’s done.
How to Create an Image Conversion Folder in Automator
- Launch automaton from the Applications folder.
Click on New Document.
- Choose Folder Action as your document type.
At the top of the workflow area, click the drop-down menu next to The folder action receives files and folders added to: then select Other….
Select the folder you want to assign the convert image action to. In our example, we choose the Downloads folder.
- Of Library sidebar on the far left, select Pictures.
- Of Shares column, drag Change the type of images (the one with the Preview icon) to the workflow area.
A dialog prompt will appear. If you want your action to convert copies of images placed in the folder and preserve the originals, select Add. If you want it to convert the original images, select Do not add.
- In the Change the type of images action panel, choose the type of format you want to convert the images to. We select JPG.
From the Automator menu bar, select File -> Save… or press Orderscall your new file action “Convert Image”, then click To safeguard.
That’s all we can say about it. The next time you want to convert an image to your preferred format, just drag it into the folder you assigned the action to.
Now that you know how to create the image conversion workflow in Automator, you might want to turn it into a standalone “application”, the option you can find in Automator’s new document menu.
An “Application” is a self-executing workflow that acts like a droplet – any files or folders dropped into it are used as input to the workflow. In other words, you can add an “Application” to your Dock and drop images into it for conversion.
Article link: How to create an image conversion folder in macOS