The Page Speed Service could speed load times by between 25 percent and 60 percent, Google said.
"Page Speed Service fetches content from your servers, rewrites your pages by applying web performance best practices, and serves them to end users via Google's servers across the globe," said Ram Ramani, engineering manager, in a post on the Google blog.
"Your users will continue to access your site just as they did before, only with faster load times," he explained. "Now you don’t have to worry about concatenating CSS, compressing images, caching, gzipping resources or other web performance best practices."
The system doesn't support Flash, streaming audio or video, or any files over 50MB, but such content would simply have to be hosted on a different domain.
The Page Speed Service was being offered on a trial basis for free, but Google would eventually start charging for it. While it hasn't announced rates, Google promised "pricing will be competitive".
Google said that page load times affected page ranking.
What if my site breaks?
The answer: "We hope you don’t run into this, but if it does, please contact us through the available support means we have listed in the community page."
That page contained links to a bug reporting system, user forums and step-by-step guides, but no actual contact details.
The service's terms also gave Google "a worldwide, royalty-free, and non-exclusive license to reproduce, adapt, modify, translate, publish, publicly perform, publicly display and distribute any content which you submit, post or display on or through, the Services."
It stated, "this license is for the sole purpose of enabling Google to display, distribute and promote the Services".
Google has a few demos up here and you can check how much faster it would make your site here.