Health-tracking smart ring maker Oura has filed to list on the Nasdaq stock exchange in New York, the San Francisco-headquartered company revealed on Thursday. Founded in Finland in 2013, Oura has built a loyal following among wellness enthusiasts and celebrities, including Jennifer Aniston, Prince Harry, Kim Kardashian and Tom Holland, who use its rings to monitor metrics such as heart rate, temperature and sleep quality. The listing, expected as soon as later this month, marks a significant step for a firm whose valuation is anticipated to comfortably exceed the $11bn it commanded when it last raised funds.

The filing revealed a fast-growing, high-margin business, with revenue reaching $1.21bn in the nine months to 30 June, up 74% year on year, and the company recently turning profitable with $60.8m in earnings over that period, against just $1.6m a year earlier. Its subscription service, costing $5.99 a month or $69.99 annually on top of rings priced between $349 and $499, has proved especially lucrative, doubling its user base to 5 million and generating $240.5m in revenue with 89% gross margins. Subscribers, who are predominantly women and check the app more than 3.5 times a day on average, helped Oura amass almost 42bn hours of biometric data across 50 health metrics.