I then set the format of the image to JPEG and adjust the quality until the file size is just under 70 KB (kilobytes). I first make sure the Where option is set to my directory for temporarily saved images called Landing Area. The dialog pops up and I go through my options.

To do this I select the top image, go to File, and chose Export near the bottom. Once the resizing has happened it’s time to export each image individually and set it’s compression level. Once I’m done I click the OK button and the change is adjusted on all the selected images. In this case the Width would show 750 as you just set all the images to the same width while the height would all be different and wouldn’t show a number like above. If you were resizing multiple differently sized images the fields would only show a number if they all match. Once I leave the Width field the Height field is automatically adjusted to keep the image’s aspect ratio the same. This way it was easier to see the larger photos and I could better compare, delete, and crop any images I wanted to. I then highlighted all of them, right-clicked, and opened them in Preview.

Each time I started out by moving all of the photos I potentially wanted to use into a directory, also known as a folder, so they’d all be in one place outside of the Photos application. My previous process when going through the photos I potentially wanted to use on my blog relied heavily on the Preview application. Resizing and Compressing Images Using Preview on My Mac…. In case you’re also interested I figured I’d go through how I resized and compressed my images individually using the Preview application on my Mac computer before then going over how I now use ImageMagick ® through my terminal to resize and compress all of the images in my directory at once. Two of the blog posts I found helpful while learning included an article called A few basic (but powerful) ImageMagick commands by Sunny Srinidhi in 2017 on Medium and Smashing Magazine’s article called Efficient Image Resizing With ImageMagick by Dave Newton.

After installing it, using Homebrew through the terminal, I was able to figure out how to resize a single image and then worked on compressing all the images in my directory (or folder).

I mentioned the bug to Matt while lamenting over what I should do and he recommended I look into ImageMagick ®. Back when the quality slider in the Preview application stopped working for me when exporting images on my Mac I realized I wasn’t quite sure how to compress the images I needed to upload to my website’s server.

How to resize image mac