The wide applicability has been found in the pharmacological activity of benzimidazole derivatives especially in the anti-inflammatory and painkilling properties. The present work is the report of a number of new benzimidazole derivatives prepared by a one-pot condensation reaction between o-phenylenediamine, and a variety of substituted aldehydes and acids. Subsequent products were identified through IR spectroscopy, NMR, and mass spectrometry on structural confirmation. The anti-inflammatory and analgesic effect of the synthesized compounds was done by pharmacological screening through a carrageenan-induced paw edema and acetic acid-induced writhing model in Swiss albino mice. Chronic inflammation and pain were also substantially inhibited by a number of derivatives, especially those that possess electron-withdrawing group at the 2-position, culminating with the same effect as diclofenac (p < 0.01). The in silico research based on molecular docking produced high-binding affinities in terms of COX-2 and TNF-alpha receptors tallying with the in vivo results. The initial toxicity analysis showed that these derivatives had good therapeutic tolerance. In this structure-activity relationship (SAR) undertaking, the significance of particular substitutions on benzimidazole scaffold is highlighted, thus leading to fantastic creation of benzimidazole-based therapeutics as possible substitutes of non-steroidal anti-inflammatory drugs (NSAIDs).