String s = "Rama"; byte[] bytes = s.getBytes(); StringBuilder binary = new StringBuilder(); for (byte b : bytes) { int val = b; for (int i = 0; i < 8; i++) { binary.append((val & 128) == 0 ? 0 : 1); val <<= 1; } binary.append(' '); } System.out.println("'" + s + "' to binary: " + binary);