Curtain coater for discharging coating medium in the form of a curtain moving substantially under the force of gravity onto a moving paper or board web, comprising a hopper, which has a first cavity extending along a discharge width, to which the coating medium is fed via at least one feed line, and a metering channel which discharges the coating medium via an outlet slot as a curtain, wherein the metering channel (2) is broken down into a large number of individual guide channels which, on the inlet side and along the discharge width, adjoin the first cavity (1) with pipe sections (2.1) spaced apart from one another, it being possible for the lengths and opening widths of the pipe sections (2.1) to be chosen in order to even out the flow resistance along the discharge width, and, in the flow direction (S), the pipe sections (2.1) in each case changing into a diffuser (2.2) for the sectional flows from the guide channels to be led together on the outlet side.