Abstract: The present invention relates to a turbomachine component (1) or collection of components comprising at least a first and a second blade (3I, 3E) and a platform (2) from which the blades (3I, 3E) extend, characterized in that the platform (2) has a non-axisymmetric surface (S) bounded by a first and a second end plane (PS, PR) and defined by at least two class C construction curves each one representing the value of a radius of said surface (S) as a function of a position between the pressure face of the first blade (3I) and the suction face of the second blade (3E) in a plane substantially parallel to the end planes (PS, PR), these including at least one upstream curve and one downstream curve; each construction curve being defined by at least one pressure face control end point and one suction face control end point such that: —the tangent to the downstream curve at the suction face control end point 20 is inclined by at most 5°; —any other tangent to a construction curve at a control end point is inclined