This paper presents a new technique for efficiently calculating and remove indistinguishable states in finite-state automata. A central problem in automata theory is to minimize a given Deterministic Finite Automaton (DFA). DFA minimization is an important topic because it can be applied both theoretically and practically, in for instance compilers. Minimizing a DFA increases its efficiency by reducing its amount of states and it also enables us to determine if two DFAs are equivalent. A DFA(deterministic finite automata) have some redundant state that means this type of state doesn‟t participant for generating useful strings. And these types of state are called dead state, unreachable state or indistinguishable state. In deterministic fini...