How to Batch Resize Images: Best Methods for Windows, Mac, and Phone

When you need to resize multiple images at once, manual editing is not an option. Processing each file individually in Photoshop can take time and increase the risk of errors.

In addition, image resizing can mean different things depending on your goal. You might want to compress images to reduce their size. Or, you may need to adjust the canvas size so every image has identical dimensions.

Because of these differences, choosing the right tool is essential. To simplify the process, this guide explains how to batch resize images on Windows, Mac, Android, and iPhone, using various practical tools.

Part 1: What Type of “Batch Resize Images” Are You?

Many users who want to mass-resize images either need to standardize dimensions of multiple images, compress file sizes, or achieve both tasks at once.

For example, an e-commerce operator may want to standardize product image dimensions so they are perfectly uniform before publishing on platforms like Amazon.

In contrast, a website admin who wants all web pages to load faster will need to batch compress images to reduce their sizes, such as 5MB files to 500KB files.

However, many free tools do not offer dedicated options to address these needs. Therefore, you should first identify your exact goal before selecting a tool.

Consider the following scenarios to understand your situation.

• Scenario 1: Uniform Dimensions: You want all your images to have the same width and height. This need is common for e-commerce sellers and social media managers. In this case, you need a tool that supports resizing by pixels, percentage, and cropping.
• Scenario 2: File Size Compression: You need to reduce the file size for storing or sharing, regardless of how the dimensions change. For this purpose, you need a tool that lets you set a target file size for compression.
• Scenario 3: Balancing Both: You need to resize multiple images at once while also controlling the output file size. This requires a tool that combines dimension controls with quality and format settings in a single workflow.

Part 2. How to Batch Resize Images on Windows/macOS?

If you’re looking to batch reduce image file sizes in Scenario 2, UPDF offers the best solution. It is an AI-driven, complete PDF editor available across Windows, Mac, iOS, and Android.

On your desktop, UPDF lets you batch compress images by five compression levels based on the image quality and file size you need. Before saving the files, you can also view the estimated output size to balance image quality and storage requirements more accurately.

In addition, UPDF includes built-in cloud storage. After compressing images on your desktop, you can save them to UPDF Cloud and access them from your phone, tablet, or other connected devices. As a result, you can manage and sync resized images across all platforms.

That said, the steps to compress images are the same on both Mac and Windows. Let’s review these.

Steps to Batch Resize Images with UPDF Desktop

Step 1. Open UDPF and click “Tools” from the bottom. Then, select the “Reduce File Size” option under Multi-File Operation (Batch Process).

Step 2. Click “Add Files” to upload your desired image files to UPDF.

Step 3. Once uploaded, go to the Compress panel on the right and click the Maximum Quality dropdown menu.

Step 4. Select your desired image quality from the options. You can also click “Click to calculate” to preview the output image size. Then, click “Save.”

Step 5. Click “Apply” from the right panel to save your resized images.

Note: UPDF also supports image compression on mobile devices. It offers four compression levels based on file size and compression speed. However, the mobile app does not support batch image resizing, and the compressed images are saved as PDFs. Resizing images in PDF is also supported on UPDF.

Part 3. How to Batch Resize Images on Windows 11/10/8/7?

Many Windows users think they need to manually batch-resize images in Photoshop. However, you can do it easily using dedicated batch processing tools such as Microsoft’s official PowerToys or various third-party options.

PowerToys Image Resizer:

PowerToys is Microsoft's official app that allows you to resize multiple images by pixels and percentage. It offers various size presets, along with the option to custom-create new presets.

Here are the steps.

1. Download and open Microsoft PowerToys and enable the Image Resizer tool.
2. Select your images and right-click. Then, choose “Resize with Image Resizer.”
3. Click the presets dropdown and choose your preferred size from the small, medium, large, and phone options.
4. Adjust other settings if needed and click “Resize.”

IrfanView Batch Processing:

InfanView allows you to resize multiple photos by pixels, percentage, cropping, and more. Moreover, you can convert files into 20 image formats.

Here’s how it works.

1. Download and open IrfanView and click “File.” Then, choose “Batch Conversion/Rename” from the list.
2. Locate your images using the right panel. Then, click “Add all” to select them.
3. Click the Output format dropdown and choose your desired format.
4. Select “Use advanced options for bulk resize” and click the “Advanced Options” button.
5. Adjust the image dimension settings under the Resize section and click “OK.”
6. Set the output folder and click “Start Batch” to proceed.

FastStone Photo Resizer:

FastStone is a free app that allows you to batch convert and rename multiple images. Before exporting, you can resize images by pixels, percentage, print size, and the dimensions of one side of the image.

Follow these steps to batch-resize images.

1. Download and open the FastStone app and go to the folder containing your images.
2. Select the desired images and click “Add” from the right.
3. Check “Use Advanced Options” and click the Advanced Options button.
4. Select the Resize option. Then, choose a method for resizing.
5. Set the resize dimensions and click “OK.”
6. Choose an output folder and click “Convert” to resize all images.

Part 4. How to Batch Resize Images on macOS?

To batch resize images on Mac, you can either use built-in tools such as Preview and Automator workflow or third-party apps such as Freshly Squeezed.

Preview App Batch Adjustment:

With Mac Preview, you can open multiple images and adjust their size by width, height, and image resolution.

1. Select the images to resize in Finder. Then, click “File” and choose “Open.”
2. Select all images and click “Tools” at the top. Then, choose “Adjust size.”
3. Set the image dimensions for all images and click “OK.”

Automator Workflow:

If you're working with a large batch of images, the Automator app allows you to batch-resize images for free by creating an automatic workflow.

1. Open the Automator app and select the “Quick Actions” option.
2. Select “Photos” and drag “Scale Images” to the workflow window.
3. Click “Add” to allow copying of original files.
4. Set a folder to save copied images. Then, customize the image scaling size.

• Go to “File” and click “Save.” Rename the action as “Resize Photos” and click “Save.”
• Select the images you want to resize. Then, right-click and choose “Quick Actions.”
• Select “Resize Photos” from the list and click “OK’ to proceed.

Freshly Squeezed:

Freshly Squeezed is a user-friendly app that allows you to resize images by their aspect ratio, dimensions, and quality.

1. Open the Freshly Squeezed app on Mac and drag and drop your images to its interface.
2. From the right panel, adjust the image ratio, dimensions, and quality as needed.
3. Set an export folder and click “Export images.”

Also Read: Check How to Resize PDF Size on Mac

How to Batch Resize Images on Your Phone?

If you’re working on your smartphone, you can use the following apps to resize images.

PhotoFlow: Batch Processing App for iOS

PhotoFlow lets you resize images by width, height, aspect ratio, and more.

1. Open the PhotoFlow app and tap the “+” button to add your images.
2. Tap the “Settings” icon at the top and adjust the resize settings.
3. Then tap the file view icon at the top to view your images.
4. Tap the “Share” icon and choose where to save the resized images.

Pixelcut: Mobile AI Batch Processing for Android

Pixelcut is an AI-driven photo editing app with the option to batch-resize images by adjusting their canvas size.

1. Open Pixelcut and select the “Batch Edit” tool.
2. Select all the images you want to resize and tap “Add.” Then, tap on “Resize.”
3. Then, select the desired image dimensions and enable “Aspect fill” if needed.
4. Tap the “Share” icon at the top and set export settings. Then, tap “Download images.”

Wrapping Up

Batch resizing images doesn't have to be complicated, whether you need to standardize dimensions, compress file sizes, or do both at once. Every platform has reliable tools to get the job done. However, if you want one solution that handles all three scenarios seamlessly across Windows, Mac, iOS, and Android, UPDF is the clear choice. Download and try UPDF today!