A verifiable duplex multiplier circuit is provided. In one mode, the circuitry of the duplex multiplier functions as an N-bit×N-bit multiplier. In another mode, the circuitry of the duplex multiplier operates as dual N/2-bit×N/2-bit multipliers. Because the same circuitry can be used to serve as both an N×N multiplier and as dual N/2×N/2 multipliers, integrated circuit resources are conserved. The duplex multiplier circuitry uses an architecture that can be automatically synthesized using a logic synthesis tool. Verification operations can be performed using logic-equivalency error checking tools. Exhaustive verification is possible using this approach, even when relatively large duplex multipliers (e.g., duplex multipliers with N values of 16 or more) are used.