The invention relates to an impeller (10) for a rotor of a turbocharger, comprising blades (12) and a wheel back (16) which adjoins the blades (12) in the axial direction of the impeller (10). The wheel back (16) has a first sub-region (26) with a first thickness (B) and a second sub-region (24) which adjoins the first sub-region (26) radially outwards and has a second thickness (A), wherein the quotient of the second thickness (A) and the first thickness (B) equals 0.85.
