You see, WordPress creates several different image sizes from the one image that you upload (your theme will use thumbnails, featured image sizes, etc). I used to try to compress images in Preview on a Mac but this was an inefficient and tedious process. This is easily done with a plugin called ShortPixel. However, if you are uploading images to a blog or website – you should also compress your images to make the file size even smaller. This process reduce the image file size somewhat. In this post I am talking about how to resize the actual dimensions of your photo. I leave scaling and resampling checked and hit Ok. However, if you plan to print your images at large sizes – it is best to keep the resolution number high if it comes up that way. I keep mine at 72 which is a good size for the web. It is a best practice to resize your image to a reasonable size for the web before uploading it to your blog. Generally WordPress will automatically resize a large image to fit your template BUT large image sizes will slow your site down – even thought the photos look ok online. Now click on “Tools” in the top menu bar and click on “Adjust Size” from the drop down that opens up. Preview will open both of these file types. Most of the images that I use for this blog are in. This is true even on a Mac despite all of the time machine capabilities. Whenever you plan to edit an image it is always best to work with a copy of the original file, in case you don't like the results. There are different image editing websites like PicMonkey and Canva that let you resize images – but the easiest method, in a pinch, is using Preview on a Mac (and you thought it was only for PDF's) How to Resize Images on a Mac Without a Photo Editing App 1.

If you are a blogger knowing how to resize images on a Mac (sorry, I don't do Windows), is a real timesaver.

For example, if you want pictures to look good in your Twitter stream (horizontal), they need to be a different dimension than images that you use for Pinterest (vertical). I do this because every social media site has a different ideal image size for photos. You may have noticed that I use many different image sizes in my posts on this blog. For bloggers, this is a quick and easy method of getting the image sizes that you need for your blog posts. This is how to resize an image on a Mac using Preview.

Resize image for youtube channel mac