A simple chemosensor, 4-amino antipyrine linked bis-1,2,3-triazole, was synthesized via the “click” approach using the CuAAC method and characterized by FTIR, NMR, and ESI-MS spectroscopy. The synthesized chemosensor upon ion sensing study showed a selective and significant detection of Hg(II) and Cu(II) ions, with the LOD being 56 and 63 μM, respectively. Mercury and copper are toxic heavy metals. The quantitative and qualitative detection of these ions is paramount for human health and the environment. The effect of time and temperature on the binding capability of APT with Hg(II) and Cu(II) ions was also studied using UV-Vis spectroscopy. Additionally, DFT studies lay forward the structural optimization of the chemosensor by the (B3LYP)/6-311G(d,p) and B3LYP/LanL2DZ level of theory.