SAN FRANCISCO — Google is giving away the restaurant ratings compiled by its recently acquired Zagat review service as part of an expansion of its listings for local businesses.

The changes announced Wednesday eliminates an annual $25 subscription fee that Zagat had been charging for online access to its surveys of diners. Those diners have rated about 35,000 restaurants in more than 100 cities around the world.

The Internet fees helped protect sales of the burgundy-colored guidebooks that Zagat has been selling since its 1979 inception. For now, Zagat still intends to sell the guidebooks.

Google Inc. bought Zagat for $151 million in September to compete against Yelp’s popular online rating service. Google and Yelp Inc. are battling to attract more traffic to spur more sales of ads to neighborhood merchants