Oxygen (branded on air as Oxygen True Crime) is an American cable and digital multicast television network owned by the NBCUniversal Media Group unit of NBCUniversal, a division of Comcast. The network primarily airs true crime television series and police procedural dramas.

The channel launched on February 1, 2000, under the ownership of Oxygen Media, a consortium including Geraldine Laybourne and Oprah Winfrey among other stakeholders. It originally carried a format of lifestyle and entertainment programming oriented towards women. Oxygen Media was acquired by NBCUniversal in 2007 for nearly $1 billion, after which the channel began to place a stronger focus on targeting young adult women. After the network experienced ratings successes with a programming block dedicated to such programming, Oxygen was relaunched in mid-2017 to focus primarily on true crime programs and crime dramas. Oxygen is among the NBCUniversal channels to be spun off into Versant in 2025.

The channel initially operated as a cable network; in 2022, Oxygen began to also operate as a digital multicast television network on subchannels of NBC Owned Television Stations. As of November 2023^[update], Oxygen is available to approximately 59 million pay television households in the United States, down from its 2012 peak of 80 million households.

The privately held company Oxygen Media was founded in 1998 by former Nickelodeon executive Geraldine Laybourne, talk-show host Oprah Winfrey, media executive Lisa Gersh, and Carsey-Werner producers Marcy Carsey, Tom Werner and Caryn Mandabach. Laybourne was the company's founder, chairwoman, and CEO, remaining with the channel until the NBCUniversal sale. The company's subscription network Oxygen launched on February 1, 2000.

Oxygen's first headquarters were at Battery Park City in New York City, near the World Trade Center. During the September 11 attacks, the network temporarily went off the air; a simulcast of Time Warner Cable-owned regional news channel NY1 was carried by Oxygen's channel space until the studio reopened within a week after the attack. Oxygen's operations were later consolidated at Chelsea Market, a former Nabisco factory at 15th Street and Ninth Avenue in New York City.

Prior to 2005, the channel carried a limited schedule of regular season WNBA games produced by NBA TV. The channel later began to focus chiefly on reality shows, reruns, and movies. For a time during the talk show's syndication run, Oxygen aired week-delayed repeats of The Tyra Banks Show. The yoga/meditation/exercise program Inhale was the last inaugural Oxygen program on air into the channel's NBC Universal era, albeit in repeats; it was cancelled in 2010.

Several original reality series targeting women also aired on the network, including Campus Ladies, Bliss, Oprah After the Show, Talk Sex with Sue Johanson, The Janice Dickinson Modeling Agency, Snapped, Girls Behaving Badly and Bad Girls Club. Oxygen launched with immediate DirecTV carriage at launch, and was added to Dish Network in early 2006, during that provider's carriage conflict with Lifetime.

In August 2007, rumors emerged that NBCUniversal had made offers to acquire Oxygen, with the network reportedly recommending that Bravo Media head Lauren Zalaznick lead the network post-acquisition. It was reported that the network had been pursuing offers of at least $1 billion (referred to internally as "BET money", in reference to Viacom's earlier acquisition of the channel). On October 9, 2007, NBC Universal announced it would be acquiring Oxygen for $925 million.