How to resize photos on Mac without installing applications

A Mac computer can be a very good team with which to make photo editing, being able to perform works with very powerful and advanced tools. But, of course, a Mac is also very valid for simpler and simpler actions such as resizing an image. The latter is something that sounds very simple, but probably many users do not know how it is done natively in macOS. Therefore, in this post we will help you access this tool and discover the odd ones that are very interesting.

How to resize photos on Mac with Preview

Preview is the name that the native Mac application receives in which, as you have already guessed by its name, you can open and find a preview of your images. This application is installed as standard on macOS, so it will not be necessary in any case to have to download and install it . In some system updates functionality and tools have been added for it, but in essence it is still a simple and intuitive application.

There are two ways to open Preview, both end up taking you to the same place but by different paths. You can go to the launchpad or press cmd + space to search for the application and open it. Once you are in it, a window will open in which to search for one or more images to open. Although there is a shorter way to reach it, and it is by going to the folder where the image is and clicking twice on it. The latter in case you have the Preview option enabled as the default application to open photos, but you will have to press the right button and click on Open with> Preview.

To resize a photo from Preview you must have the photo in question open and go to Tools> Resize , all from the toolbar at the top. Once here you will see that a box appears in which you will be allowed to change the size of the image with several measures , which are pixels, percentage, inches, centimeters, millimeters and points. You can perform a proportional rescaling, that is, the image continues to maintain the same proportion of width by height, or you can freely choose these values yourself without depending on each other. The latter is done by unchecking the “Proportionally resize” box.


From the same box of resizing images you can also have access to a series of standard measures that may serve you. You can also enable or disable the option to sample the image and check its weight with the information provided at the bottom of the window. In short, this is a simple and quick way to resize your photos on the Mac without having to open a more powerful editor or install it if you don’t have it.

Without delving into it, we can highlight that from Preview you can get to do many other useful functions in some cases. For example, adjust the colors of a photo, crop it to eliminate parts that we don’t need or rotate it so that it stays in the view that interests us.