RnBass (also spelled as R&Bass, shortening of rhythm and bass)^[1] is a music genre that fuses contemporary R&B music with hip hop production style or music genre, known as ratchet music,^[2][3] coined by DJ Mustard.^[4]

Described by Vibe magazine as a breath of fresh air for the R&B genre, RnBass consists of tonal singing, melodic harmonies, along with heavy 808's bass elements.^[5] There are also notable elements of EDM, with influences of 1990s–2000s music, as well as hyphy.^[6][7] Coined by Bay Area producer J Maine,^[8] the RnBass musical style has garnered critical attention since the early-to-mid 2010s and has been popularized with urban audiences across America by Los Angeles producer DJ Mustard, by mixing pop music elements of ratchet with turn-up lyrics.^[2] Despite originating in the West Coast, namely the Bay Area, RnBass producers and artists across the globe continue to develop R&B with the modern RnBass genre.

YouTube producers like Starra and Skylark Beats have been heavily pushing the genre online with their various remixes, tutorials and RnBass instrumentals. Also, its cross-genre influence has spread into the mainstream.^{[citation needed]}