In this work, a simple, fast, and accurate optimization approach based on a differential evolution (DE) algorithm is presented to obtain for the synthesis of coplanar strip (CPS) lines. The results obtained from the synthesis formulas proposed in this work are compared with the results of quasi-static analysis and the other synthesis formulas previously published in the literature. The accuracy of the proposed synthesis formulas is found to be better than 1.22% for 2524 CPS somples. (c) 2006 Wiley Periodicals. Inc.