The invention relates to a root extraction circuit comprising a plurality of n sub circuits, the m th sub-circuit thereof consisting of m+ add/subtract cells. The two add/subtract cells in each sub circuit which process the least-significant bits in said sub-circuit always receive a logic signal "1" on their "b" data input and always operate as an add cell. The remaining add/subtract cells of an m'" sub-circuit are controlled by the carry signal output of the add/subtract cell which processes the most-significant bit in the (k-1) th sub-circuit. As a result of the foregoing steps, the root extraction circuit requires only add/subtract cells, so that a very regular lay-out pattern can be obtained when the circuit is integrated.