How to reduce the size of image files on a Mac

Reducing the size of image files is essential. The less they weigh, the better, especially when we are going to insert them into a web page or we are about to send them through an email message.

We are going to need an application to achieve this on more than one occasion, whenever we have one or several images of great weight and we are going to share them, as we have already indicated, through email, include them on a website or send them through the social networks, among other possibilities.

Some time ago we already told you about the tool that serves as the basis for this review, now we return to talk about said application in order to analyze its high capabilities. Although we use it mainly to optimize the images that we upload to our website, it is also valid for use in other sections.

How to work with ImageOptim?

The operation is very simple, after downloading and installing ImageOptim , whenever we want to reduce the size of one or several image files, we only have to open the folder that contains it or contain it and select them.

After running the application, we just have to drag the selected image or images to its interface. The optimization process will begin immediately. We will see how the size of each file is reduced, in percentage, in the Reduction column . If we leave the default settings as they are, the new images will overwrite the original ones.

If we have a Windows computer, we can resort to an application with similar characteristics. We mean Riot . Its work is similar, although it does not work in the same way. It is a simple application that takes care of adapting the resolution of the images to store them on the hard drive or to upload them to a web page.

How to use ImageOptim in WordPress?

When you select an image, housed in a folder on your computer’s hard drive, that you are going to upload to the web, you must, before completing the process, optimize it with ImageOptim .

If you want to optimize already uploaded images, you must download them to your computer via FTP and proceed with their optimization before uploading them again. (Remember that images are, by default, hosted in folders within wp-content -> uploads . Those folders are sorted by year and month.)

Using ImageOptim on the web will increase the rating of your website by known systems (Page Speed, WebPagetest, Pingdom Tools and GTmetrix), which brings with it a better set-up when it comes to search engine indexing.

To consider

It is convenient to optimize all copies of the image that you have uploaded and those that have been created, in different sizes, by WordPress. Remember that for this you must use the system that we explained above, using an FTP client. Although the ideal is to proceed with the optimization before uploading the original image to the server, when it is inserted into the web page.

If you do not want to do this work, remember that you can use one of the three plugins that we propose below: WP , EWWW Image Optimizer or Imagify Image Optimizer . Although it does not hurt to make a previous reduction with ImageOptim , or with Riot , in the event that we use a computer with Windows, as we have indicated.


To get the application that we propose and use it on a computer with macOS, you must access ImageOptim .