In E major, the 12-bar blues is E7 | E7 | E7 | E7 | A7 | A7 | E7 | E7 | B7 | A7 | E7 | B7. The 12-bar blues: four bars of I, two of IV, two of I, then V–IV–I and a V turnaround. The base of blues, rock and roll and much of jazz.
The library above is set to 12-Bar Blues in E major. Press Play to hear it with strummed guitar, bass and drums in a blues shuffle groove, tap any chord to hear it on its own, or pick another key or a capo.