Which punk offshoot genre is characterized by extremely fast tempos and short songs?

The punk offshoot genre characterized by extremely fast tempos and short songs is hardcore punk.

Hardcore punk developed in the late 1970s as a more intense, faster, and often more aggressive extension of first-wave punk. Its songs were commonly brief, with stripped-down guitar riffs, forceful drumming, shouted vocals, and lyrics addressing politics, alienation, violence, and social frustration.

The style emerged in several scenes, including Los Angeles, Washington, D.C., New York, and the United Kingdom. American bands such as Black Flag, Minor Threat, and Bad Brains helped define its sound and DIY ethic. British groups including Discharge pushed the music toward an even harsher approach that later influenced crust punk and extreme metal.

Hardcore punk is sometimes confused with skate punk, which often uses fast tempos but developed a distinct connection to skateboarding culture and melodic songwriting. Post-punk, by contrast, generally explored more experimental textures and rhythms rather than simply increasing punk's speed and intensity.