if you have recently ran a Google PageSpeed Insights test, you may have come across the red warning: "Serve images in next-gen formats.. This is the most prevalent reason that pulls down mobile performance scores in 2026.
What Does This Warning Actually Mean?
Google marks your site when Google identifies the classic image formats such as JPEG and PNG. Your pictures may be good but Google thinks they are bloated as they take more time to download and decode than the current versions such as WebP.
The dreaded "Serve images in next-gen formats" warning in a Lighthouse report.
How to Fix the Error Using NoLoginTool (3 Steps)
You don't need complex plugins or expensive software to fix this. You can satisfy Google's requirements in under 60 seconds using our client-side converter.
.webp files to your server and update your image tags. Run the PageSpeed test again; you will see the warning disappear and your performance score jump!
Why Not Just Use High Compression JPEGs?
You can just compress your JPEGs, however, that is not enough. With high compression you get artifacting (blurry blocks in your image). WebP has a better algorithm with edges and smooth gradients having a much lesser file size.
Eliminate the PageSpeed warning right now.
Fix My Images NowFinal Checklist for 2026 SEO
- Turn all the Hero and Banner images into WebP.
- Always include
widthandheightattributes in your pictures to avoid layout drifts (CLS). - Apply
loading="lazy"to below the fold images.