Aimed primarily at small businesses, Google reckons that it takes only three steps and few minutes to sign up and deploy the service.
The platform allows users to integrate search into personal and community sites and blogs, and developers can use the Google Custom Search APIs to allow searching from within their applications.
"For many organisations, a website is their window to the world and significant investment goes into attracting customers to the site," said Robert Whiteside, UK and Ireland enterprise manager at Google Enterprise.
"Keeping visitors on a site once they arrive, however, is a challenge and the absence of a search facility can be a major cause of a lack of website 'stickiness'.
"By improving the ease, speed and accuracy with which users can find what they need, businesses can ensure that their website justifies the investment."
Google has released two versions of the platform. Custom Search is a free ad-supported engine, and Business Edition is a paid-for service which offers more customisation and support.
Both versions provide site search hosted by Google, eliminating the need for a business to install and maintain its own technology, and reporting features provide insights into visitor behaviour.
The Business Edition also caters for full customisation of search results, email and phone support and a choice about whether to include ads or not.
Google Custom Search Business Edition starts at around £50 per year for searching up to 5,000 pages, and extends to approximately £1,125 per year for up to 300,000 pages.
Larger volumes of pages are supported through Google's enterprise sales group.
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