System design using accurate performance models may include generating, using a processor, a performance verification testbench from a hardware description language design and an automaton and determining, using the processor, a parameter of the design by analyzing the performance verification testbench using formal verification methods. The parameter is provably accurate. A performance model of a system under design including the design may be executed. The performance model uses the parameter. A determination may be made, using the processor, whether the system under design meets a system requirement according to a comparison of a result of executing the performance model with the system requirement.