How do I automatically optimize new uploads?

New images are optimized automatically, in the background, the moment WordPress finishes saving them. This is on as soon as you install SlashImage, so there is nothing to set up.

Turn automatic optimizing on or off

1. Go to Media > SlashImage.
2. Scroll to the Compression section.
3. Switch Auto-optimize on upload on to optimize every new upload, or off to leave new uploads untouched.
4. Click Save changes.

Each upload is queued the instant WordPress saves it and optimized a few seconds later. The upload itself stays instant, because optimizing happens after the file is saved rather than holding it up. The SlashImage column in your Media Library then shows how much smaller each image got.

What can go wrong

• A new upload was not optimized. Only JPEG, PNG, WebP, and AVIF are optimized. Other types are skipped and show Format not supported. See Which image formats can SlashImage optimize?.
• You turned it off and want to catch up. You can still optimize a single image from the Media Library, or optimize everything at once with a bulk run. See How do I optimize images I already uploaded?.

See also

• How do I optimize images I already uploaded?
• What does the SlashImage column show?
• Which image formats can SlashImage optimize?