In a turbine for an exhaust gas turbocharger having a turbine housing which has a first and a second spiral channel with the second spiral channel extending over a wrap angle range of less than 360 degrees of a turbine wheel of the turbine, and the first spiral channel having a larger wrap angle range than the second spiral channel and the spiral channels being arranged adjacent each other in at least one angular range which includes the wrap angle ranges, the nozzle has an overall nozzle width via which exhaust gas is admitted to the turbine wheel over a respective partial nozzle width of the spiral channels wherein the partial nozzle width of the first spiral channel is greater than the partial nozzle width of the first spiral channel in the first angular range, at least in a further angular range of the wrap angle range which is different from the at least one angular range.