How To Delete Desired Image Sizes From wp-content/uploads?

My default media setting in WordPress blog is 150×150, 300×300, 1024×1024 respectively for thumbnail, medium, large images. Now I am designing a theme that need different size thumbnail images to show in theme. For this, I go to the media setting again and changed the setting with my news sizes like 72×72, 250×250, 400×400 respectively for thumbnail, medium, large images.

But now to resize my old uploaded images, I used Regenerate Thumbnails WordPress plugin and that generated my new media setting images size easily. So this solved my main problem.

Main Question:

Now the main problem that just occurred is that my hosting space is now going to end. When I checked my files then found that I have 7 images of one image and from that I am only using 4.

first-image-name.jpg
first-image-name-72x72.jpg
first-image-name-150x150.jpg
first-image-name-250x250.jpg
first-image-name-300x300.jpg
first-image-name-400x400.jpg
first-image-name-1024x1024.jpg
second-image-name.jpg
second-image-name-72x72.jpg
second-image-name-150x150.jpg
second-image-name-250x250.jpg
second-image-name-300x300.jpg
second-image-name-400x400.jpg
second-image-name-1024x1024.jpg
...............................
---------- and so on ----------

Now I want to delete 150×150, 300×300, 1024×1024 sizes images. For this many recommend me DNUI (Delete not used images) and Clean Up Images WordPress plugins but they are not picking those old image sizes.

Q:) So How To Delete My Desired Image Sizes From wp-content/uploads folder?

A quick and easy fix for this is to make use of a plugin called Force Regenerate Thumbnails (to which I don’t have any affiliation to)

Unlike a plugin like Regenerating Thumbnails, Force Regenerate Thumbnails creates all your new custom sizes and delete all redundant/orphaned sizes.

Force Regenerate Thumbnails allows you to delete all old images size and REALLY regenerate the thumbnails for your image attachments.