Peloton, best known for its exercise cycles, announced Wednesday it has filed with securities regulators for an initial public offering.

Peloton, which filed the paperwork confidentially, said it has not yet decided on the number or price range of shares it expects to sell. Companies with less than $1 billion in revenue can file confidentially under the JOBS Act.

The company makes cycles and treadmills with screens for users to join live and recorded fitness classes from their homes, hotel rooms or offices. CEO and co-founder John Foley has described Peloton as a fitness, technology and media company.

Peloton was founded in 2012 and sold its first spinning bike in 2014. Cycles retail for $2,000 and treadmills sell for $3,995. Subscriptions to access classes cost $39 per month. The company also started selling digital memberships last year for people to access workout classes without buying any of Peloton's equipment.

Peloton raised $550 million last year, bringing its total outside funding to $1 billion and valuing the company at $4 billion. The company's investors have included Tiger Global Management, L Catterton, Fidelity and TCV, according to Crunchbase.

2019 has been a busy year for IPOs. Uber, Lyft and Pinterest are among the companies that went public in the first half of the year.

Disclosure: CNBC parent Comcast-NBCUniversal is an investor in Peloton.