[10] It was discovered on 6 September 1997 by Brett J. Gladman, Philip D. Nicholson, Joseph A. Burns, and John J. Kavelaars using the 200-inch Hale Telescope together with Sycorax and given the temporary designation S/1997 U 1.

Caliban's diameter is estimated to be around 42 km, based on thermal measurements by the Herschel Space Observatory.

[7] Somewhat inconsistent reports put Caliban in light-red category (B–V = 0.83 V–R = 0.52,[12] B–V = 0.84 ± 0.03 V–R = 0.57 ± 0.03[11]), redder than Himalia but still less red than most Kuiper belt objects.

[13] Measurements of Caliban's light curve by the Kepler space telescope indicate that its rotation period is about 9.9 hours.

[7] Caliban is hypothesized to be a captured object: it did not form in the accretionary disk that existed around Uranus just after its formation.