No personal experience at any of these clubs (unfortunately), but here is what I found in my 2005 Lonely Planet Paris guidebook. I'm sure the prices are out of date.
Cafe Universel, 267 rue St-Jacques; admission free. The Universal Cafe attracts a mix of students and jazz lovers with its live music, with everything from bebop and Latin sounds to vocal jazz sessions.
Le Baiser Sale, 58 rue des Lombards; admission free-€22. The Salty Kiss is one of several jazz clubs on the same street. The salle de jazz (jazz room) on the 1st floor has concerts of pop rock and chansons at 7pm and Afro-jazz and jazz fusion at 10pm. The cover charge depends on the act; it's free during the soiree boeuf (jam session) on Monday night.
Le Caveau de la Huchette, 5 rue de la Huchette; adult €10.50 Sun-Thu, €13 Fri & Sat. Housed in a medieval caveau (cellar) that was used as a courtroom and torture chamber during the Revolution, this club is where virtually all the jazz greats have played since the end of WWII. It's touristy, but the atmosphere can be more electric than at the more serious jazz clubs.
Le Duc des Lombards; www.jazzvalley.com/duc; 42 rue des Lombards; admission €12-20. A cool venue decorated with posters of jazz greats (including the eponymous Duke), this place attracts a far more relaxed (and less reverent) crowd than the other jazz clubs in the same street.
Le Petit Journal St-Michel; www.petitjournalstmichel.com; 71 blvd St-Michel; admission €15.25-40. The "Little Newspaper" is a sophisticated jazz venue, with everything from Dixieland and vocals to big band and swing.
L'Opus, 167 quai de Valmy; admission free-€15. Housed in a former officers' mess by the Canal St-Martin, the Opus has moved from hip-hop to the cool sounds of jazz, soul, blues, gospel and zouk (a blend of African and Latin American dance rhythms).
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