How to Resize an Image on Mac

Post processing is pretty much an essential part of photography. No matter how much time you spend taking a photo or how carefully you compose it, you still may have to tweak it a little in post. It doesn’t have to do with just color correcting images and fixing exposure. You may feel the need to resort to post processing even if you wish to accomplish a seemingly simple task like resizing your image.

What is Resizing a Photo?

If you want to resize pictures on Mac you should know that it can mean more than one thing. In order to physically resize your photo, you can either crop it or enlarge it. But maybe you simply need to change the file size of your image, and not necessarily the aspect ratio or field of view that it has. In that case, you need to know how to change the resolution of your image to make it smaller. This is important if you like to post your photos online, as some social media platforms don’t allow images with huge file sizes to be uploaded.

Let’s take a look at both ways to resize an image on a Mac computer.

How To Resize an Image on Mac Using Preview

Changing an image’s dimensions is the easiest way to resize an image on Mac. Here is a brief guide:

1. Open your image in the built-in Preview app; 

2. Choose Markup Toolbar > Adjust Size and enter new values for width and height. Alternatively, you can click the “Fit into” pop-up menu and choose a size.

3. Now, there are several ways to adjust your image. You can choose any preferred option:

• Resize by Percentage: Select 'percent' from the pop-up menu next to the Width and Height fields, then enter your desired percentage.

• Maintain Proportions: To keep the image's original proportions, check 'Scale proportionally'. Changing one dimension (width or height) will automatically adjust the other to maintain the aspect ratio. Selecting a size from the 'Fit into' menu may result in one dimension being smaller than the chosen size to keep the image proportional.

• Resizing Without Losing Detail: To change dimensions without losing any detail, deselect 'Resample image' before adjusting the width or height.

The other method to make an image smaller is to crop it. Cropping an image can be done with almost every image editing program you have on your Mac. Remember that you can work with almost any format: JPEG, TIFF, PNG, etc. 

Here is a brief guide on how to resize an image on your Mac using the aforementioned Preview app: 

1. Simply open the image in Preview.

2. Go to Tools.

3. Select the Crop option to make your image smaller.

Cropping not only cuts into your image but also makes the overall size smaller. You can also use more advanced programs like Apple Photos or Luminar Neo to crop your images. These programs give you a little more control over your images, but essentially their crop tools work the same way as Preview.

The quickest way to resize an image, if you need to make it smaller, is to crop it. Cropping an image can be done with almost every image editing program you have on your Mac. Remember that you can work with almost any format: JPEG, TIFF, PNG, etc. The easiest way to do it is to use Mac Preview to resize the image: 

• Simply open the image in Preview.
• Go to Tools.
• Select the Crop option to make your image smaller.

Cropping not only cuts into your image but also makes the overall size smaller. You can also use more advanced programs like Apple Photos or Luminar Neo to crop your images. These programs give you a little more control over your images, but essentially their crop tools work the same way as Preview.

How to resize a PDF image on Mac? It's very simple. Here's a quick tutorial:

• Open the PDF in Preview.
• Select "Tools" from the menu and choose "Adjust Size."
• In the "Adjust Size" window, modify the width and height of the image as desired.
• Ensure the "Resample Image" option remains unchecked to preserve image quality.
• Click "OK" to confirm the changes.
• To save the resized PDF, go to "File" and select "Export."
• Give the exported file a name, choose PDF as the format, and select a location to save it.
• Click "Save."

You can also use third-party applications. Adobe Acrobat and Foxit PhantomPDF offer a resize option. You can use them to increase or reduce the file size.

Enlarge Your Images in Luminar Neo

How to resize a JPEG image on Mac? The best way to enlarge your photos on a Mac is to use Luminar Neo. You can essentially drag and increase the photo sizes in multiple image editors, but Luminar Neo gives you more control over the output quality of your enlarged photos. Another plus is that you can do this while exporting a picture. In order to make your photos larger in Luminar Neo, follow these steps:

• Find the picture you want to export in the catalog and select it.
• Open the File menu and select Export.
• In the Resize dropdown menu, choose Long Edge.
• You will see a field where you will need to enter the size you want in pixels. 
• After that, you need to choose a color space and format.
• Now click Save. Voila! You get a picture of the right size.

The reason Luminar Neo is better than most photo editors on your Mac for enlarging photos, however, is the number of resampling options you have while changing the Image Size. You can resize the picture not only when exporting, but also using Crop AI.

Make the Image Size Smaller for the Web

If all you need to do to resize a photo on Mac is to reduce the file size of your image, Luminar Neo has got you covered there as well. 

The quickest way to resize an image on Mac is to use the built-in Preview app. Simply follow our step-by-step guide:

1. Open your image in the Preview app;

2. Click on Tools > Adjust Size, then choose Resample image;

3. In the Resolution field, enter a smaller value.

That’s it! Now, the new size of your photo is shown at the bottom. Not hard at all, right?

How To Resize an Image on a Mac Without Losing Quality

To resize pictures on a Mac while maintaining their quality, follow these steps using the Preview app:

• Open the image you wish to resize using Preview.
• Select "Tools" from the menu and choose "Adjust Size."
• In the "Adjust Size" window, modify the width or height of the image as desired.
• Ensure the "Resample Image" option remains unchecked to preserve image quality.
• Click "OK" to confirm the changes.

How do you resize a photo on Mac without Preview? Luminar Neo also has an image quality slider. Just move it to the desired number during editing, and then you'll get the picture in the quality you want.

Another way how to resize a picture on Mac is to save the file in HEIC format. It can only be opened on the Mac. Yes, you won't increase the number of pixels, but you will keep the original image quality. The beauty of this format is that it has the same quality as JPEG, but is half the image size.

How to Resize Multiple Images on Mac

Mac users can easily process multiple photos. To resize an image with Preview on Mac, follow these steps:

• In a Finder folder, select all the images you wish to resize.
• Right-click on them and choose "Open With..." then select Preview.
• In Preview, you will see one selected image in the center and the rest as thumbnails on the side. Select all the thumbnails by pressing "Command + A".
• Go to the Preview menu bar at the top and click "Tools", then choose "Adjust Size...".
• In the pop-up window, set your resize settings and click "OK".

These are some of the easiest ways you can resize your image on your Mac. There are a plethora of software programs that you can use for these kinds of purposes, and a little research about their features will reveal all that you can do with them. However, the methods mentioned here are some of the most efficient ones to achieve exactly what you want. Use any of them, and you're sure to succeed!

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