A method for identifying cookware on an induction cooktop having coils, includes the steps: (a) acquire a coverage factor matrix; (b) set a present level at a maximum value of the matrix; (c) count closed iso-level curves corresponding to the present level and save the result; (d) decrease the level by an amount; (e) count closed curves corresponding to the decreased level; (f) when the number of closed curves at the present level is not lower than that from the previous level, update the saved result with the present level; (g) when the number of closed curves at the present level is lower than that from the previous level, keep the previously saved result; (h) repeat steps (d) to (h), until the number decreases; (i) assign coils inside the curve to a distinct cluster; and (j) use the clustering to estimate a position, shape, size, and orientation of the cookware.