Reduce Image Size on Mac: Using Preview and 4 Alternative Methods

Why Is Reducing Image Size on Mac Important? 

Large-sized images can take up a significant amount of storage space. If you use graphics for work or personal projects, you’ll understand the struggle of managing a hard drive filled with high-resolution images. Reducing image size can save significant storage space, allowing you to keep your Mac storage optimized.

In addition, size is important for sharing and uploading images online. Websites and social media platforms often restrict the size of the images you can upload. Large image files can also slow down your website’s load time, affecting the user experience and your website’s SEO ranking. 

Finally, sending large images via email can be a hassle. Most email clients limit the size of attachments. By reducing the image size, you can ensure that your images can be sent without issues. 

This is part of a series of articles about image optimization.

In this article:

• Reducing Size on Mac Using the Preview App
  • Step 1: Open the Image with Preview
  • Step 2: Select the Adjust Size Tool
  • Step 3: Enter the Image Dimensions
  • Step 4: Set the Resolution
  • Step 5: Save Changes and the Image
• Compress Multiple Photos into a ZIP File
• Compress an Album with Photos
• Compress Images Photos in a Word Document
• Automate Image Compression with Cloudinary

Reducing Size on Mac Using the Preview App 

Mac’s built-in Preview app can be used for various purposes, including reducing image size. Let’s walk through the process step-by-step.

Step 1: Open the Image with Preview

The first step is to open the image with Preview. To do this, right-click the image you want to resize and select Open With > Preview. This will open your image in the Preview app. You’ll see the image displayed in the Preview window, ready to work on it.

Step 2: Select the Adjust Size Tool

Once your image is open in Preview, go to the menu bar at the top of the screen. Click on Tools and then select Adjust Size. This will open a new window where you can change the dimensions and resolution of your image.

Step 3: Enter the Image Dimensions

You’ll see different options in the Adjust Size window. In this window, you can alter the width and height of your image.

Step 4: Set the Resolution

Next, you’ll need to decide on the resolution, which is measured in pixels per inch (ppi). A higher resolution will result in a higher quality image, but it will also increase the file size. For most web and email uses, a resolution of 72 ppi is sufficient.

Step 5: Save Changes and the Image

Once you’re satisfied with your image’s new size and resolution, click OK to close the Adjust Size window. Then, go to File in the menu bar and click Save to save your changes. Note that this will overwrite your original image, so if you want to keep the original size, save a copy before resizing.

Compress Multiple Photos into a ZIP File

One of the easiest and most straightforward ways to reduce image size on Mac is by compressing a folder of photos into a ZIP file. This method is particularly helpful when you want to share multiple photos through email or save space on your device. However, this won’t mean that your images will be smaller once unzipped–they’ll go back to their original size once you do, making this best for sending files back and forth.

To compress a folder of photos into a ZIP file, you need to gather all the images you want to compress into one folder. Once you’ve done that, control-click or right-click on the folder and select Compress. A ZIP file will then be created in the same location as the original folder. This file contains all the images you’ve compressed, but its size is significantly smaller than the original images. 

Compress an Album with Photos

If you store and manage your photos using Photos (formerly iPhoto), you can also use these apps to compress an album. This can be useful when you want to share an entire album with others or if you need to free up some storage space on your Mac.

To compress an album using Photos, open the app and select the album you want to compress. Then, go to the File menu and select Export. In the export settings, you can choose the format and quality of the photos. By selecting a lower quality or a smaller size, you can significantly reduce the size of the images.

After you’ve selected your desired settings, click Export and choose where to save the compressed photos. The new images will be smaller in size but still maintain decent quality.

Method 4: Compress Images Photos in a Word Document

Using Microsoft Word on Mac to compress images might seem like an unusual method, but it can be helpful when you’re dealing with documents that contain a lot of images.

To compress photos in a Word document, open the document and click on a photo. Then, go to the Picture Format tab and click on Compress Pictures. A dialog box will appear where you can choose the resolution of the images. The lower the resolution you choose, the smaller the image size will be.

Once you’ve selected the resolution, click OK, and the images in the document will be compressed. This method can greatly reduce the size of your Word documents, especially if they contain graphics, making them easier to share and quicker to load.

Method 5: Automate Image Compression with Cloudinary

Reducing image sizes on macOS is essential for developers striving for optimal media performance. By understanding the various built-in tools and techniques available, you can ensure your images are efficiently optimized, leading to faster load times and better user experiences.

One powerful solution for image optimization is Cloudinary. Cloudinary is a cloud-based service that simplifies media management by offering robust tools for image upload, transformation, optimization, and delivery. With Cloudinary, you can automate compressing and optimizing images, ensuring they are always served in the best possible format and size.

To get started with Cloudinary, you need to sign up for an account and obtain your API credentials. Once you have these, you can set up a Python script to automatically upload and compress images. Cloudinary’s advanced features, such as automatic format selection and quality adjustment, ensure your images are always optimized for the best performance.

Wrapping Up

Optimizing image sizes on macOS is a crucial step for developers aiming to enhance media performance. Leveraging tools like Cloudinary simplifies this process and provides powerful capabilities to manage and optimize your media assets effectively. By implementing automated solutions, you can focus more on development and less on manual media optimization, ultimately delivering a faster, more engaging user experience.