How to Batch Resize Images on a Mac

Are you looking to resize your images on a Mac? You may have difficulty because images do not always come in convenient sizes.

If so, you will be relieved to know that a solution already exists on your device.

In this article, we will batch resize images on a Mac using a variety of tools.

What is resizing?

When you resize an image, you resize it by decreasing or increasing the total number of pixels. However, resizing is synonymous with reducing the size of an image because resizing to achieve a larger image usually results in an ugly, blurry-looking image. For example, you could have a width of 800 pixels by 640 images and reduce it to 480 pixels wide by 300 pixels high.

The good thing about changing the size is that you don’t cut anything. In other words, it doesn’t change the amount of data in the image.

Why would you want to resize your images?

Image size matters. And that’s particularly true if you intend to upload your images to the Internet to display on a website. Larger images take longer to load on a web page. Nobody wants to watch an image load slowly and painfully.

Even if you want to use your images in a PowerPoint presentation, you’ll need to make sure you can fit as many images as you want into your slide deck and still not end up with a huge file that will take ages to present. .

Resizing is also useful when you want to send images via email. In Gmail, for example, you can’t email a file larger than 25 MB. You can only send a larger file using Google Drive.

How to Batch Resize Images on a Mac

Resizing hundreds or thousands of images can take hours if you decide to work on one image at a time. Fortunately, you can batch resize your images easily on a Mac. And best of all, you don’t even need a third-party tool to do it.

Mac computers come with two pre-installed image resizing programs that are easy to work with: Preview and Automator. Let’s see how each software works.

How to Batch Resize Images on a Mac with Preview

Preview is a powerful yet easy-to-use software that is designed to resize multiple images in one go. Is that how it works:

1. In Finder, click all the images you want to resize, and then open them with the Preview app. To do this, select all images, then right click and then select “Open with” and click “Preview”. At this point, Preview will display all the selected images in the thumbnail drawer on the left side. You can scroll through the list to see specific items in the main panel. You can even refine your images further by removing any elements you may have selected by mistake.
   
2. In Preview, select all the images that you want to batch resize from the thumbnail drawer on the left side. To do this, click “Edit” and then “Select All.”
   
3. Click “Tools” and then click “Adjust Size.” This will open a new window where you will be asked to enter various details about the images.
   
4. Proceed to enter the desired width and height values. The app also allows you to select the most common default dimensions. To use them, click “Fit to” and then select the dimensions you want from the drop-down box. If you want to resize just one dimension, say the height, be sure to select “Scale proportionally.” Otherwise, you’ll end up with images that are disproportionately scaled.
   
5. Click “File” at the top and select “Save All.” Images in Preview will instantly resize to your desired resolutions. But if you want to keep the original images as they appear in the thumbnail drawer on the left, choose “Export” or “Save As.”
   

And voila! You have newly created images that you can share with family and friends or upload to a website.

How to Batch Resize Images on a Mac with Automator

Automator allows you to resize images with just a few clicks, even if you have no coding skills. If you haven’t used Automator before, don’t worry. We will guide you through the process step by step. This is what you should do:

1. Open the applications folder and launch Automator.
   
2. From the resulting menu, choose “Service/Quick Action.” In Automator, services are programs that you can run to perform various tasks, including deleting files, setting desktop images, and resizing images.
   
3. Click “Workflow receives update.”
   
4. From the resulting drop-down menu, select “Image Files.”
   
5. In the sidebar, click “Files and Folders.”
   
6. Press and hold “Get specified finder items” and then drag it to the workflow panel.
   
7. In the sidebar, click “Photos” and then drag “Scale Images” to the workflow panel.
   
8. At this point, the app will ask you if you want to save the original files to a separate folder by adding a “Copy Finder Items Action.” If you don’t want to do that, just click “Don’t add.”
   
9. Enter the desired size value in the Scale Images action panel.
   
10. In the menu bar, click “File” and then select “Save.” You can think of any name for your new service. For example, you could call it “Resize Image.”
    
11. Click “Save.”
    

After successfully creating a resizing service, you can use it to resize images as many times as you want. You just need to click open “Finder” and open the service by clicking on its name.

How to reduce the size of multiple JPEG files on a Mac

If you work with a lot of JPEG images, you may want to resize them to a consistent size to ensure they fit your blog or website. Here’s how you can do it:

1. Select all the images you want to resize and then open them with the Preview app.
   
2. In Preview, click “Edit” and then click “Select All.”
   
3. Click “Tools” and then select “Adjust Size.”
   
4. Proceed to enter the desired width and height values.
   
5. Click “File” at the top and select “Save All.” Images in Preview will instantly resize to your desired resolutions.
   

How to Batch Resize Photos on Mac Using Lightroom

Lightroom is your go-to software when you need to generate multiple images in a fixed size. You’ll find it extremely useful when you have a big shoot coming up and want to create extra space on your camera cards. Here’s how you can batch resize photos on Mac using Lightroom:

1. Open the Applications folder and launch Lightroom.
2. Import the photos you want to resize.
3. Within Lightroom, make any other adjustments you want to your photos before resizing.
4. Select all the photos you want to resize.
5. Click “File” in the top menu and then select “Export.”
6. Choose a location where you would like to send your photos.
7. Choose a batch name for your exports.
8. Limit the pixel size by checking the “Resize to fit” box. Then proceed to enter the desired width and height.
9. Click “Export.”

All your resized photos will be sent to your chosen location.

Additional FAQs

How do I reduce the size of multiple images at once on Mac?

You can batch resize images on Mac using Preview or Automator. Both applications come pre-installed on your computer and all you need to do to open them is launch the applications folder.

How do I convert multiple JPEG files on my Mac?

Preview can convert JPEG files to many file types, including PDF, PNG, and PSD.

To do it:

• Select the image you want to convert and then open it with the Preview application.

• Click “File” in the Preview application and then select “Export.”

• Click “Format” and then choose the desired file type.

• Choose a name or a new location for the converted file, and then click “Save.”

If you want to convert more than one file at a time, open Finder, select all images and then right-click and select “Open with” and then select “Preview”. From this point, follow the steps above to complete the process.

How do I resize multiple images on my Mac at once?

To resize multiple images on Mac at once, you need to open them with Preview and then do the following:

• Click “Tools” in the top menu and then click “Adjust Size.”

• Proceed to enter the desired width and height values.

• Click “File” at the top and then choose “Save All” from the drop-down menu.

The Right Resizing Tools

Resizing images has many benefits, and if you have a Mac, you have several tools to do it. Although using the built-in resizing tools can be a little complicated at first, the entire process is easy to master after a few rounds.

What is your experience with Preview? Between Preview and Automator, which one do you feel most comfortable working with?

Let’s chime in in the comments section below.