Silencing any doubts about its chances on the public market, Amazon.com (AMZN) ended the day $54 million richer as its long-awaited initial public offering soared 30 percent above its opening price.

Propelled by demand that pushed opening trading to 29-1/4, the pioneering online bookstore hit a day's high of 30 before settling down to close at 23-1/2. That was more than 30 percent higher than the $18 target price set by underwriters just the night before.

Even that pre-IPO price had been raised twice before the market opened. Initially, it had been set for a $12-to-$14 range, then got bumped up to $14 to $16 before the company's investment bankers settled on the $18 price.

The IPO raised $54 million for Amazon, giving the company a market value of $438 million. The online bookstore put 3 million shares on the block.

This latest turn of events increases Amazon's IPO capital and market value by 12.5 percent over what it would have received had it launched at $16 a share.

The online bookseller is riding an IPO resurgence that has reclaimed the market in the last two weeks. Rambus (RMBS) launched a highly successful offering yesterday, and technology publisher CMP Media last week registered for an IPO in the near future.

Some analysts say this new wave could drive more filings for technology IPOs and prompt those companies that have already registered to move forward with their launch.

Richard Peterson, an IPO analyst with Securities Data, said technology IPOs in the same price range have averaged first-day gains of 42 percent since the early 1990s. Some examples are Cisco Systems, the former Lotus Development, and Open Market.

Amazon.com also upped the number of shares that underwriters Deutsche Morgan Grenfell, Hambrecht & Quist, and Alex. Brown had the option to purchase to 450,000 from 375,000.

Amazon.com's plans to go public have been watched closely in the financial and high-tech industries as a barometer of market interest. The company is a pioneer in electronic commerce.

Despite the volatility of the stock market, particularly that surrounding technology stocks, "There is probably an expectation [surrounding Amazon.com's IPO]. Booksellers are doing quite well, and Amazon.com just might be able to piggyback on that popularity," Peterson said.

The amended filing counters concerns of a move this week by competitor Barnes & Noble, which launched its own online bookstore. In addition to its Web venture, the brick-and-mortar bookstore behemoth filed a lawsuit this week against Amazon.com over claims that it is advertising itself falsely as the world's largest bookstore.

Amazon.com reported net revenues of $16 million and a loss of $3 million for the quarter ending March 31.

Amazon.com said its average daily visits have grown to 80,000 in March 1997 from 2,200 in December 1995, and that repeat customers account for more than 40 percent of orders.