A new derivatives of isonicotinohydrazide 9 (a-e) and 10(a-e) were designed, synthesized, characterized based on the different spectroscopic analysis FT-IR, -1H, -13C-NMR, mass spectra, and also elemental-analyses, and identified as a remarkable anti-inflammatory along with analgesic effect. In-vitro and in-vivo anti-inflammatory and analgesic actions were performed using analgesic acetic acid-induced squirming and Hot plate latency tests using male Swiss albino mice. The study was supported by the in-silico and ADMET approaches. Among the series, compound (10e) showed the highest IC50 value for COX-1 inhibition, whereas compounds (9e) and (10e) exhibited the highest COX-2 SI. Further, in silico studies provide a putative bind site for the potent compound in a three-dimensional geometrical view. The results revealed that the title compound (10e) with bromo group exhibited potent COX-2 inhibitor at different times which is on par with the normal drug used in the assay system. Substitution of halogens at N’(2-phenoxyacetyl)nicotinohyrazide showed (10e) potent analgesic outcome on acetic acid-induced squirming response and thermal pain among the series 9(a-e) and 10(a-e). The overall pharmacological result suggests that the newly synthesized compounds possess good anti-inflammatory along with analgesic-activity which was evaluated through in-vitro, in-vivo, and --silico studies.