The importance of metal nanoparticles in various fields has led to the consideration of various methods for their synthesis in the present using physical and chemical techniques. However, both of these techniques are time-consuming, costly, and hazardous to the environment. Due to their non-toxic nature and extensive synthesis, biological methods are very advantageous. In the current study, aqueous stem extracts of Caltropis procera and Amaranthusa scendens were used for synthesis of silver nanoparticles (SNPs) from silver nitrate. The plant extract functions as a capping and reducing agent. The quantitative formation of AgNPs was observed using UV-visible spectroscopy. The reduction of Ag⁺ to AgNPs by plant extract capping material was confirmed by Fourier transform infrared spectroscopy. The silver nanoparticles had a strong signal, as indicated by the EDX spectrum. SEM analysis revealed the irregular shape of the bioengineered silver nanoparticles. The synthesis of AgNPs using C. procera and A. ascendens, with average sizes of 14 nm and 25 nm, respectively, was visible in images taken using a transmission electron microscope. Utilizing the well diffusion method, these biosynthesized silver nanoparticles were evaluated for their ability to inhibit the growth of bacteria and fungi. The AgNPs produced from extracts of C. procera and A. ascendens exhibited the highest antimicrobial activity against Bacillus cereus and Aspergillus niger.