Quote from: fevirfevir on April 16, 2016, 08:40:31 PM

From reading the wiki (https://en.bitcoin.it/wiki/Block_hashing_algorithm), a block hash is 256 bits.

Out of curiosity, I copied a block hash (block 125551, just a random pick) and turned it into binary, see:
$ echo 00000000000008a3a41b85b8b29ad444def299fee21793cd8b9e567eab02cd81 | xxd -b -c 4
0000000: 00110000 00110000 00110000 00110000 0000
0000004: 00110000 00110000 00110000 00110000 0000
0000008: 00110000 00110000 00110000 00110000 0000
000000c: 00110000 00111000 01100001 00110011 08a3
0000010: 01100001 00110100 00110001 01100010 a41b
0000014: 00111000 00110101 01100010 00111000 85b8
0000018: 01100010 00110010 00111001 01100001 b29a
000001c: 01100100 00110100 00110100 00110100 d444
0000020: 01100100 01100101 01100110 00110010 def2
0000024: 00111001 00111001 01100110 01100101 99fe
0000028: 01100101 00110010 00110001 00110111 e217
000002c: 00111001 00110011 01100011 01100100 93cd
0000030: 00111000 01100010 00111001 01100101 8b9e
0000034: 00110101 00110110 00110111 01100101 567e
0000038: 01100001 01100010 00110000 00110010 ab02
000003c: 01100011 01100100 00111000 00110001 cd81

Now I'm counting 4 columns (2nd untill the 5th), 16 lines, and 8 characters per set. 4*16*8=512 bits.

I must be missing something obvious, but haven't found it, yet. Pointing out the obvious is appreciated. Thanks.

You read the hash as string and the characters are the binary of the ascii characters. What you want to do is convert the hex to a binary number,