I'm confused why after Google's July 2018 PageSpeed Insights tool update with bias to mobile seems to recommend serving images in "Next Gen Formats" like JPEG 2000, JPEG XR, or WebP?

Almost no one uses these formats and many browsers don't even fully support them (all) if at all. JPEG 2000 has been around for a long time now and is basically a "failed" mainstream replacement for JPEG--it never took off. So why is Google even recommending this change to increase site performance? On my personal site, the tool seems to indicate I take a 2.5s hit in load time because I'm not serving my images in "next gen" formats.

2 Answers 2


Google is speed oriented organization and WebP is Google invented image format. I assume, that they just want that developers are more often happy to use these formats, especially WebP which is supported in more and more browsers. My personal opinion is that Google is thinking about the future of data, that all these images are using loads of data storage what needs to be saved somewhere. So, why not to recommend to use WebP format and in the same time promote it which means as more websites will start to use these formats, then more browsers will fully implement support for these formats as a standard of the web.

If you look in the future of the web, the data are taking more storage space by requiring larger storage infrastructure for servers etc. So new generating formats could help in the future to optimise potential issues in data storage infrastructure. As the data are taking more and more space in a web globally which will require more energy use, more servers, more storage etc. And all these potential issues with the growing value of data could be related to global warming as data storage could require more and more energy.

Recent research conducted by StorageCraft revealed the worries of IT decision makers on these fronts. 43 percent of respondents said they are struggling with data growth now and believe it is going to get worse.

Organizations well outside the Fortune 500 realm that used to be gigabyte scale data storage shops are now petabyte-scale storage shops, facing challenges they never expected, said Brockett. More and more businesses will need high-performing and scalable systems that intelligently store and also protect massive quantities of data over extended periods.

According to StorageCraft’s research, though, 51 percent of respondents know they would benefit from more frequent data backup but are unable to do so because their existing IT infrastructure doesn’t allow it. More than half are not confident that their organizations’ IT infrastructures can perform instant data recovery in the event of a failure.

Source: http://www.dataversity.net/future-data-storage/

Probably these data storage issues won't feel average website owner, but looking in a bigger scale globally, it's very important to promote and look for new ways to store and deliver data in formats which use less space. In this case, new formats for images are part of the potential solutions for data storage infrastructure requirements in the future.

I have a couple of websites which are fully supported with WebP and depending on a browser can serve prefered JPEG if required. The saving in real life could be even more than 70% based on my personal experience.


why after Google's July 2018 PageSpeed Insights tool update with bias to mobile seems to recommend serving images in "Next Gen Formats"

There are actually two questions:

  1. why ... seems to recommend serving images in "Next Gen Formats". Because next gen formats are faster and Google want to push all, webmasters and browser vendors, to use them, because the proceeding of previous gen formats costs Google more time and efforts.

  2. why after Google's July 2018 PageSpeed Insights tool update with bias to mobile ... Wrong question imo: the usage of next gen formats was recommended by PageSpeed Insights tool before update too.

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