Abstract We present statistical analysis of blocks in the binary expansions of Feigenbaum constants α and δ for the logistic map. The analysis is carried out on both 1016 and 3400 bit expansions. A χ2 test is applied for lumping data and a serial test is applied on gliding data. Contrary to a previous research by Karamanos and Kotsireas, our test results did not indicate any evidence to reject randomness of these constants. Additional 25 randomness tests also support the conjecture of randomness of these constants having transcendental character.