The present invention relates to a cutting insert for a cutting tool for the chip-removing high feed milling machining of workpieces, the cutting tool having a holder with a seat for receiving the cutting insert, the cutting insert having at least one cutting edge lying in a covering surface. To achieve a higher feed speed and greater cutting depth, particularly during high feed milling, there is provision, according to the invention, whereby the cutting edge has in portions three different radii of curvature, a first portion having the smallest radius, a middle second portion adjoining it having the largest radius, and a third portion adjoining the latter having a medium radius lying between the smallest and the largest radius, and whereby a peripheral line, running through all the cutting edges, of the covering surface is exclusively convexly curved. The invention relates, furthermore, to a correspondingly configured holder and to a cutting tool.