Lazzarini was born in Milan, specifically in the Calvairate district, where he developed a passion for music at a young age. This passion led him to study piano at the renowned Giuseppe Verdi Conservatory in Milan. As he grew older, he transitioned into the world of hip hop, joining the Zero2 and Blocco Recordz collectives. In 2009, he participated in the annual Italian hip hop event Tecniche Perfette.
On November 5, 2012, he released his debut mixtape album Destiny Mixtape, which was followed by his second mixtape K1 Mixtape in 2014. The latter was produced by DJ Telaviv of Blocco Recordz and featured collaborations with other notable Italian rappers. In the same year, Lazza collaborated with Emis Killa on the singles "Bestie" and "Bella idea," which were included in Killa's album Keta Music Vol. 2.
April 14, 2017, marked the release of Lazza's debut studio album Zzala, which showcased a unique blend of trap sounds and classical piano influences. The album spawned two platinum-certified singles, "MOB" and "Lario," and was promoted through a tour that spanned two seasons. In the following months, Lazza focused on producing tracks for other Italian artists, including Ernia, Nitro, and Salmo.
Preceding the release of his second studio album Re Mida, Lazza dropped several singles, including "Porto Cervo," which earned a gold certification. Re Mida debuted at the top of the Classifica FIMI Artisti chart and was certified platinum. In October 2019, two re-releases of the album were released: Re Mida (Aurum) and Re Mida (Piano Solo). The former featured unreleased tracks and new collaborations, while the latter consisted of solo piano tracks reinterpreted by Lazza.
On July 17, 2020, Lazza released his third mixtape J, which included ten tracks and collaborations with various Italian rappers. Later that year, he featured on three tracks of the mixtape Bloody Vinyl 3. On April 8, 2022, he released his third studio album Sirio, which debuted at the top of the Classifica FIMI Artisti chart and eventually achieved a double platinum certification.
On December 4, 2022, it was officially announced that Lazza would participate in the Sanremo Music Festival 2023. His entry, "Cenere," finished second in the competition.
