The critical state is arguably the most robust criterion for strength design, including post liquefaction strength. The conventional triaxial test is used for the determination of critical state parameters; however, it is time-consuming and the required set of tests is relatively expensive for common geotechnical tasks. A simplified test procedure is developed to determine the critical state line in sandy soils. The procedure is reliable, economical, and fast. In order to verify the simplified test procedure, results are compared against critical state parameters determined in conventional triaxial tests. The comparison shows very good agreement between critical state parameters obtained with the suggested procedure and those gathered with triaxial testing. Limitations are identified.