In November, Forbes published an article confirming Christopher Comstock as the individual behind the Marshmello project, with regards to existing proofs such as his real name being revealed in music royalty manager BMI’s database and that Marshmello’s company was registered in August 2015 under Comstock in Delaware. Furthermore, it was also disclosed to Forbes by industry insiders that the two are the same person. Previously-known pieces of evidence such as the ASCAP credit, their physical and musical similarities, and Skrillex addressing Marshmello as “Chris” were taken into account of confirming Marshmello’s identity.

His musical style includes groove-oriented, synth and bass-heavy electronic dance music. Inspired by other masked DJs like Deadmau5 and Daft Punk, Marshmello appears wearing a full-head-covering white-colored bucket. Despite the anonymity, his career received international recognition in 2015 when he began releasing tracks online, including remixes of Zedd’s “Beautiful Now”, Jack Ü’s “Where Are Ü Now” and others, as well as his own single “Alone”.

Marshmello released his debut studio album Joytime, consisting of 10 songs, via his label Joytime Collective on January 8, 2016. One single was released from the album, titled “Keep It Mello”, featuring Mexican rapper Omar Linx, and was certified gold by the Recording Industry Association of America (RIAA). The album peaked at number five on Billboard’s Dance/Electronic Songs chart, number fourteen on the US Heatseeker Albums chart and forty-one on the Independent Albums chart.

His next single, announced on Twitter, was a collaboration with American R&B singer Khalid titled “Silence”, which was released on August 11, 2017 via RCA Records. The song appeared on the Top 200 in over 28 countries. It topped the Dance charts in Australia, the United Kingdom, and the United States, and charted in the Top 10 of more than fifteen countries such as Germany, Sweden and Norway. It also appeared on the year-end charts of Hungary, Denmark, Austria, Belgium, and the Netherlands. Additionally, it was certified multi-platinum in many countries. Among them were platinum by BPI (United Kingdom) and BM (Germany), double platinum by BEA (Belgium), RMNZ (New Zealand) and RIAA (United States), triple platinum by MC (Canada), a quadruple platinum by SRIA (Sweden) and a quintuple platinum by ARIA (Australia).

Later in the year, he released his collaboration with American singer Selena Gomez, the single “Wolves” which became a commercial success, having reached the top 10 in more than 20 countries. It topped the charts in Latvia, Poland and Hungary, and the Billboard Dance/Electronic Songs chart. It was also his highest-charting Billboard Hot 100 song in 2017, having peaked in the Top 50 of over 50 countries and sold over 2.5 million copies of certified units. The song was certified gold in the United Kingdom, Germany, Portugal and Denmark, and multiple-platinum in Brazil, Sweden, Canada, and Australia while receiving single-platinum certification in the United States, France, Italy, Spain, Belgium and New Zealand.

Marshmello wears a custom helmet for public appearances. His identity was not known initially, but was confirmed to be Chris Comstock in April 2017 by Forbes, citing events such as Skrillex’s referring of Marshmello as “Chris” in an interview, the managerial connection of Shalizi, and the similar tattoos and birthday. On July 2, 2019, Marshmello released a documentary with More Than Music (Artist Spotlight Series) on YouTube. In the documentary, Shalizi describes the process and effort into creating the Marshmello brand.

In January 2018, Marshmello released a posthumous collaboration with rapper Lil Peep, titled “Spotlight”. He decided to release the single only after speaking to Peep’s mother, who had requested her son’s unpublished musical work to be released as much as possible. A month later, Marshmello worked with frequent collaborator Slushii for the song “There ×2”, which was released as a single.

Among the other singles released after the work with Anne-Marie were a song with rapper Logic titled “Everyday”, which was released as the third single from his seventh mixtape, Bobby Tarantino II, “Fly” and “You Can Cry”, a collaborative single with rapper Juicy J and British soul singer James Arthur. On June 19, Marshmello announced on Twitter his second studio album titled Joytime II, which would be musically similar to its predecessor. The album was released on June 22, 2018. Rolling Stone described it as monotonous and Marshmello’s decision to not feature guests as disappointing, stating “every song sounds like it has already been pre-leased for use by energy-drink companies or extreme-sports squads.” The album was given a ‘one-and-a-half star’ rating by the magazine, while Pitchfork gave the album a 4.2 out of 10 rating. Two singles were released off the album in June, titled “Tell Me” and “Check This Out”, the latter of which receiving an official music video published several months later.

In August 2018, he collaborated with British band Bastille to release a single titled “Happier” in August. It became his highest charting song in Canada, Sweden, the United Kingdom, and the United States, while becoming his third number-one song on the Dance/Electronic Songs chart, where it spent a record 69 weeks at the top. The song was certified gold in Belgium, Sweden, and the United Kingdom, platinum in New Zealand and the United States, and double-platinum in Australia and Canada. His subsequent singles, collaborations with Egyptian singer-songwriter Amr Diab titled “Bayen Habeit” and American rapper and producer Roddy Ricch titled “Project Dreams”, were released in December. Marshmello announced that month, he was working on his third studio album, Joytime III.

Marshmello, together with Fortnite player Tyler “Ninja” Blevins, have won prize money of a million dollars from Epic’s E3 Celebrity Pro Am charity tournament. Half of the million was donated to KIND (Kids in Need of Defense), an organization providing legal counsel to refugees and immigrant children. With the single Happier and its pet-dog-themed video, he supported the #FindYourFido campaign by American Society for the Prevention of Cruelty to Animals (ASPCA) in October 2018, also recognized as “Adopt a Shelter Dog” month.

In January 2019, Marshmello collaborated with the free-to-play video game Fortnite Battle Royale to throw an in-game concert, along with releasing merchandise based on the game. On February 2 and 3, the concert was held online, amassing over 10 million players on the first day. During the first quarter of 2019 he released various collaboration. The first, in February, was a collaboration with dubstep producer Svdden Death titled “Sell Out”. The second was with Scottish band Chvrches, called “Here with Me”. Finally, in April, he released Roll the Dice, an extended play with California rappers SOB X RBE. It contains three songs: “Roll the Dice”, “Don’t Save Me” and “First Place”.

In June 2019, he released “Rescue Me”, a collaboration with American rock band A Day to Remember as the first single from his third album, Joytime III. Following which, Marshmello revealed the full tracklist on his Twitter. The album features collaborations with producers Bellecour, Crankdat, Elohim, Flux Pavilion, Wiwek, Slushii, Tynan, and Yultron. The album was released on July 2, 2019.

On May 1, 2020, Marshmello collaborated with Halsey to release “Be Kind”. In July 2020, Marshmello featured on rapper Juice Wrld’s posthumous album Legends Never Die, on the tracks “Come & Go” and “Hate the Other Side”, which reached numbers two and ten on the Billboard Hot 100, respectively. On July 30, 2020, when asked by a fan on Twitter when his next album Joytime IV would be released, Marshmello stated “very soon”.

On September 1, 2020, Marshmello collaborated with 42 Dugg to release the single “Baggin”.