He meant approximately half a bit. Base64 uses 64 characters, which means 6 bits per character. 50 characters gives you about 5.64 bits per character. Unlike

He meant approximately half a bit. Base64 uses 64 characters, which means 6 bits per character. 50 characters gives you about 5.64 bits per character. Unlike Base64's 3-bytes-equals-4-characters, that never comes out evenly.