The invention relates to a method of shaping an ophthalmic lens to have a desired outline (11) by means of a machining device including a blocking support for the ophthalmic lens and at least one first machining tool, the method comprising the steps of: obtaining an inner cutting limit (12) for said first machining tool; defining an initial blocking position (P1) for the ophthalmic lens and its desired outline; calculating whether at least a portion of the desired outline presents a non-zero intersection (Q21-Q22) with said inner cutting limit; defining as the final blocking position (PF) either the unchanged initial blocking position if the intersection calculated the calculation step is zero, or else a blocking position that is modified relative to the initial blocking position so that the desired outline as repositioned using the modified blocking position does not present an intersection with the inner cutting limit associated with the first tool; and blocking and shaping the ophthalmic lens with the desired outline.