Generating unique 6 digit code

Question

I\'m generating a 6 digit code from the following characters. These will be used to stamp on stickers.
They will be generated in batches of 10k or less (before printing)

Answer 1

You would have 21 ^ 6 codes = 85 766 121 ~ 85.8 million codes!

To generate them all (which would take some time), look at the selected answer to this question: algorithm that will take numbers or words and find all possible combinations.