J. D. Overdrive is a southern metal band with a stoner twist from Katowice, Poland, delivering groove-laden heavy music across four albums. Their releases including Wendigo and The Kindest Of Deaths blend the swagger of southern rock with the heavy fuzz of stoner metal, establishing them in the Polish heavy rock scene.

Jack and the Bearded Fishermen is a heavy noise rock band from Besancon, France, active since 2005 with five guitarists and a rhythm section. Their fifth album Naked (2025), released through Twenty Something, showcases two decades of evolution in their guitar-dense, textured approach to noise rock and post-hardcore.

Jadira is a metal band from Tallinn, Estonia, whose releases including Desires and The Mason showcase their approach to heavy music from the Baltic underground. The Estonian metal scene's unique character infuses their compositions with a cold, atmospheric quality distinct from their Scandinavian neighbors.

Jaern is a doom metal band from Gothenburg, Sweden, established in 2019 and featuring a four-piece lineup including guitarist/vocalist Marko Brostrom. Their self-titled debut EP (2020) delivers four tracks of fuzzy, heavy doom with psychedelic and sludge elements, with the track Miasma earning particular praise from the Swedish underground doom community.

Jagannatha is an instrumental doom and stoner rock trio from Grenoble, France, creating extended psychedelic compositions since their 2016 debut. Their three albums culminating in Trimurti (2022) have earned devoted fans with meditative, heavy psychedelic jams that blend crushing doom with spacey exploration.

Jagged Vision is a metallic hardcore band from Oslo, Norway, whose album Death Is This World (2017) was recorded by Phillip Cope at Jam Room Recording Studio and mastered by Brad Boatright at Audiosiege. Their crushing sound draws comparisons to Kylesa, early Mastodon, and High On Fire, delivering hardcore sludge with inventive riffs.

Jaggu is a heavy sludge and stoner metal band from Oslo, Norway, with four albums from Revenantian (2019) through SLUGGU (2023) recorded at Red Line Studio. Their sound blends metal, sludge, and stoner rock with guest contributions from musicians like Babs Johnson of Shaving The Werewolf.

Jahvl is a stoner rock band from St. Gallen, Switzerland, who released their self-titled debut album in 2024. Their nine-track record features extended compositions that range from heavy psychedelic jams to crushing riff-driven passages, establishing them in the Swiss heavy rock scene.

Jegulja is a rock and metal band from Ljubljana, Slovenia, featuring a baritone guitar-driven sound with multiple albums including Anguilla Guerrilla and Exit Sandman. The three-piece has been active since at least 2013, cycling through several drummers while maintaining their heavy, low-tuned approach to Slovenian underground rock.