Celecoxib is an NSAID used to treat inflammatory joint conditions including osteoarthritis. In this study, we set out to create a novel microemulsion formulation for transdermal administration of Celecoxib. To choose excipients with excellent drug loading capacity, solubility of drug in different oils, surfactant, and co-surfactant was assessed in pre formulation tests. Capmul MCM C8 was chosen as the oil in the microemulsion's formulation, while labrasol and ethanol were chosen as the surfactant and co-surfactant, respectively. The concentrations of the oil phase, Smix, and distilled water used in the preparation of the Celecoxib microemulsion were calculated using pseudo ternary phase diagrams. Three tests-a centrifugation tests, a heating and cooling cycle test, and a freeze thaw cycle testwere used to determine the optimal formulation. The % transmittance, droplet size, and cloud point of the optimized formulations were also measured.Because of its high % transmittance, the MF2 formulation stands out as the best of the bunch. A minimum globule size of 35.2 nm was observed for MF-2. The zeta potential of MF2 was calculated to be +19.0mV. Compared to previous batches, the MF2 formulation demonstrated faster drug release during the in vitro diffusion test, with peak drug concentrations occurring between 4 and 8 hours after the test began. Microemulgel was created by adding a gelling agent to the microemulsion at a 1:1.2 ratio (microemulsion: gelling agent). When tested under a wide range of stability circumstances, the microemulgel (PN3) in question performed well. The microemulgel formulation (PN3) loaded with Celecoxib was shown to cause no skin irritation in an in vitro testing. Based on these findings, it seems that a microemulsion formulation of Celecoxib might be an effective formulation for transdermal distribution. Key Words: Microemulsion, Microemulgel, Celecoxib, Arthritis