Robert Klemme wrote: > irb(main):012:0> "e".rjust 10, "0" > => "000000000e" > irb(main):013:0> Neat, thanks. So: rand(36 ** 8).to_s(36).rjust(8,"0") Useful for random binary strings too: rand(2 ** 8).to_s(2).rjust(8,"0") -- Posted via http://www.ruby-forum.com/.