SAN FRANCISCO — Pinterest set a price range for its initial public offering that will value the company below its last private-market peg of $12 billion, raising questions about investor demand for prominent but unprofitable technology companies that are stampeding toward the stock market.

In an updated prospectus on Monday, Pinterest said it planned to price its offering at $15 to $17 a share. At the high end of that range, the digital pin board company would be valued at about $11.3 billion, accounting for stock options and restricted stock. The business was first valued at $12 billion in 2015, and again in 2017, by venture capitalists and other private investors.

Pinterest’s price range dampens some of the fervor over a wave of tech offerings this year, which had promised to generate piles of new wealth in Silicon Valley. It follows last month’s I.P.O. of Lyft, the ride-hailing company, which is deeply unprofitable. While the offering created a great deal of hype and Lyft’s shares rose on their first day of trading, the stock fell below its offering price on its second day of trading, as it faced questions about its business.

“People are looking at Lyft and realizing that even if the road show goes extremely well and there is a lot of demand, you can’t overprice the offering,” said Elliot Lutzker, corporate and securities partner at Davidoff Hutcher & Citron.