Metalcore is known for its use of breakdowns, in which it was preceded by heavy hardcore. Metalcore singers typically perform screaming, a vocal technique developed in the 1980s and characteristic of 1990s metalcore. Later metalcore bands often combine this with the use of standard singing, usually during the bridge or chorus of a song. The death growl technique is also popular.
The instrumentation of metalcore includes heavy guitar riffs often utilizing percussive pedal tones, double bass drumming, and breakdowns. Drop guitar tunings are often used. Most bands use tuning ranging between Drop D and A, although lower tunings, as well as 7 and 8 string guitars are not uncommon. Drummers typically use a lot of double bass technique and general drumming styles across the board. Blast beats are also heard at times. According to author James Giordano, "tempos in metalcore tend to be slower than those found in thrash metal". Many later metalcore bands would include guitar solos in songs.
1990s metalcore bands generally had a strong influence from heavy hardcore. In the 2000s, metalcore bands began to be exclusively inspired by heavy metal. Many 2000s metalcore bands were heavily inspired by melodic death metal and used strong elements of melodic death metal in their music. Malcolm Dome of Revolver wrote that without melodic death metal band At the Gates' 1995 album Slaughter of the Soul, "modern American metalcore (everyone from As I Lay Dying and Killswitch Engage to All That Remains and the Black Dahlia Murder) wouldn't even exist." Graham Hartmann of Loudwire wrote "Although metalcore broke in the early 2000s, listening to At the Gates' 1995 album feels like a Nostradamus-esque prediction of how metal would evolve."