Hi darrencss,
thank you for your feedback. We see that you have made another post here: https://www.ads-software.com/support/topic/deactivated-for-good-no-more-money-from-me/ so we will also respond to that post in this thread ??
The TinyPNG compression web interface and the WordPress plugin use the same endpoint for compressions (i.e. there should be no difference in compression speed between the two).
The reason why you might be experiencing a difference in compression time between the web interface and the WordPress plugin is that when uploading an image to WordPress, the plugin actually makes multiple compressions per image – one compression for each image size selected in your media settings (Settings >> Media).
By default WordPress generates 4 or 5 image sizes per uploaded image (depending on your WordPress version). The plugin in turn compresses each of these image sizes. If you have 4 image sizes selected in your settings, compression will approximately take 4 times longer (1 compression per image size).
In order to reduce the compression time per image please go to your media settings (Settings >> Media) and deselect all image sizes you do not wish to generate. This will drastically affect the compression time.
I should point out that some custom themes require custom image sizes (we’ve seen some themes with 10+ custom image sizes), which of course will further increase the compression time.
For testing purposes I would suggest deselecting all image sizes (expect for the original image size) and uploading an image. You should see that the compression time will match the compression time on the TinyPNG web interface for the same image.
Hope that clarifies why it might seem like the compression is taking longer on WordPress!