Background:: Higher power consumption raises chip temperature because it draws more current from the power source, which directly affects how long the batteries survive in portable devices. High temperature affects the dependability and functionality of a circuit, requiring more complex packaging and cooling strategies. One of the most significant challenges in VLSI design is power consumption. The power consumption of the circuit rises with both transistor density and chip complexity. In addition, one of the essential building blocks of hardware in the majority of VLSI applications and digital signal processing systems is the multiplier. Aims and objective:: This study aimed to design and compare array multiplier, Vedic multiplier, and Wallace tree multiplier using variable bit lengths. Methodology:: In this paper, authors designed array multiplier, Vedic multiplier, and Wallace tree multiplier using variable bit lengths. For comparison, the VIVADO tool was used to simulate and synthesize multiplier outputs. Results:: Wallace tree multipliers resulted in 31.153mW, 13.220mW, 4.099mW, and 0.988 mW of power dissipation for 16-bit, 8-bit, 4-bit, and 2-bit, respectively. The best multiplier was designed using different logic like AOI, OAI, NAND-NAND, and NOR-NOR and was compared based on power dissipation. It was observed that 2.256mW power dissipation was observed for NOR-NOR logic, which was minimal among other logics. Conclusion:: The 4-bit Wallace multiplier using NOR-NOR logic was used for FPGA implementation, which can be used in digital signal processing applications.