NEW YORK — Shares of Fitbit are up 55 percent in the first day of trading for the fitness tracking gear maker.

Fitbit’s initial public offering priced at $20 per share, slightly more than anticipated. The company sold 22.4 million shares, raising $448 million. Its stockholders sold another 14.2 million shares, worth about $284 million.

Fitbit Inc. makes devices that can be worn on the wrist or clipped to clothing. They track steps taken, calories burned and other data. It’s the biggest-selling company in the young industry. Competitors include Jawbone, Nike, Xaomi, and Garmin. The Apple Watch includes some related features.


The stock is trading on the New York Stock Exchange under the ticker symbol ‘‘FIT.’’

Shares of the San Francisco company jumped $10.98 to $30.98 early Thursday.