Comment by pixeloution

Just to add to the above comment, a diceware passphrase is MUCH harder to break than most people realize. For example, compare the possible number of combinations:

  Diceware, 6 words          2.2 x 10^23
  Diceware, 5 words          2.8 x 10^19
  Diceware, 4 words          3.6 x 10^15
  a-zA-Z0-9, symbols, 10     4.3 x 10^19
  a-zA-Z0-9, 10char          8.4 x 10^17
  a-zA-Z0-9, 8char           2.2 x 10^15

A 6 word diceware phrase has 100 million more combinations than the 8 character alphanumeric.