A blade for a rotor of a wind turbine having a substantially horizontal rotor shaft, said rotor comprising a hub, from which the blade extends substantially in a radial direction when mounted to the hub, the blade having a longitudinal direction (r) with a tip end and a root end and a transverse direction, the blade further comprising: - a profiled contour including a pressure side and a suction side, as well as a leading edge and a trailing edge with a chord having a chord length (c) extending there between, the profiled contour, when being impacted by an incident airflow, generating a lift, wherein the profiled contour is divided into: - a root region having a substantially circular or elliptical profile closest to the hub, - an airfoil region having a lift-generating profile furthest away from the hub, and - a transition region between the root region and the airfoil region, the transition region having a profile gradually changing in the radial direction from the circular or elliptical profile of the root region to the lift-generating profile of the airfoil region, and with - a shoulder having a shoulder width and located at the boundary between the transition region and the airfoil region, wherein - the blade has a blade length, wherein the blade length is at least 40 meters, and - the profiled contour comprises a local relative thickness defined as the local ratio between a maximum profile thickness (t) and the chord length (c), - the ratio between the shoulder width and the blade length being less than or equal to 0.075, characterised in that - the relative thickness (t/c) in a blade length interval of 0-0.8L is at least 22%, - wherein the blade comprises a second airfoil profile having a relative thickness of between 29% and 31% and a position of maximum thickness located between 0.28c and 0.32c from the leading edge, wherein the second airfoil profile comprises a position of maximum pressure side camber located between 0.28c and 0.32c from the leading edge, and the second airfoil profile is located between 0.30L and 0.36L, - wherein the blade comprises a third airfoil profile having a relative thickness of between 26.3% and 27.7% and a position of maximum thickness located between 0.28c and 0.32c from the leading edge, wherein the third airfoil profile comprises a position of maximum pressure side camber located between 0.255c and 0.295c from the leading edge and the third airfoil profile is located between 0.36L and 0.45L, and - wherein the blade comprises a fourth airfoil profile having a relative thickness of between 23.5% and 24.5% and a position of maximum thickness located between 0.35c and 0.39c from the leading edge, wherein the fourth airfoil profile comprises a position of maximum pressure side camber located between 0.35c and 0.39c from the leading edge and the fourth airfoil profile is located between 0.5L and 0.85L. - a profiled contour including a pressure side and a suction side, as well as a leading edge and a trailing edge with a chord having a chord length (c) extending there between, the profiled contour, when being impacted by an incident airflow, generating a lift, wherein the profiled contour is divided into: - a root region having a substantially circular or elliptical profile closest to the hub, - an airfoil region having a lift-generating profile furthest away from the hub, and - a transition region between the root region and the airfoil region, the transition region having a profile gradually changing in the radial direction from the circular or elliptical profile of the root region to the lift-generating profile of the airfoil region, and with - a shoulder having a shoulder width and located at the boundary between the transition region and the airfoil region, wherein - the blade has a blade length, wherein the blade length is at least 40 meters, and - the profiled contour comprises a local relative thickness defined as the local ratio between a maximum profile thickness (t) and the chord length (c), - the ratio between the shoulder width and the blade length being less than or equal to 0.075, characterised in that - the relative thickness (t/c) in a blade length interval of 0-0.8L is at least 22%, - wherein the blade comprises a second airfoil profile having a relative thickness of between 29% and 31% and a position of maximum thickness located between 0.28c and 0.32c from the leading edge, wherein the second airfoil profile comprises a position of maximum pressure side camber located between 0.28c and 0.32c from the leading edge, and the second airfoil profile is located between 0.30L and 0.36L, - wherein the blade comprises a third airfoil profile having a relative thickness of between 26.3% and 27.7% and a position of maximum thickness located between 0.28c and 0.32c from the leading edge, wherein the third airfoil profile comprises a position of maximum pressure side camber located between 0.255c and 0.295c from the leading edge and the third airfoil profile is located between 0.36L and 0.45L, and - wherein the blade comprises a fourth airfoil profile having a relative thickness of between 23.5% and 24.5% and a position of maximum thickness located between 0.35c and 0.39c from the leading edge, wherein the fourth airfoil profile comprises a position of maximum pressure side camber located between 0.35c and 0.39c from the leading edge and the fourth airfoil profile is located between 0.5L and 0.85L.