What are the possible characters on an Xbox code

So, Xbox redeemable codes are 25 character case insensitive strings of letters and numbers. However, it has been suggested that not all letter/number combinations might appear (eg. 0/O). In the interest of fraud detection, what is the definitive (read as: {{Citation needed}}) list of possible characters which might make up this string?

Bonus points: given these additional rules, what are the number of possible strings that could be formed.

1 Answer

I went straight to the source and just e-mailed Xbox Support. I didn't think they would answer, but to my surprise, they did respond (screenshot of email is the best proof i can give) with the invalid characters.

There are 8 invalid letters and 3 invalid digits:

A E I O U L S N 0 1 5

That leaves them with 18 valid letters and 7 valid digits:

B C D F G H J K M P Q R T V W X Y Z 2 3 4 6 7 8 9

With 25 characters needed for a code and 25 possible letters and digits, if my math is right, and it's entirely possible it is not, that's (18+7)²⁵ which my calculator says is 8.8817842 × 10³⁴, which equals a whole lot of different combinations.

Screenshot of the e-mail from Xbox Support: