Rules for Video Game Serial Keys

Here are the rules for serial keys used in the video game industry, please follow them when creating and using serial keys in your game.

1. Never used letters and numbers that can be mistaken for other letters and numbers. Basically this rule means do not use 0 (zero) and O (the letter 'oh') at all in your generated key. Yes, you can put a slash through the zero or something, so that it looks different from the letter 'O'. That doesn't help the person who has a key that doesn't have both for him to compare them. He just sees a circle for the 'O' and doesn't know that your zero has a slash. It is okay to use a 1 (one) and I (capital 'i'), because you can make each look distinct in a way that by just seeing one of the two, the user knows which one it is. The mistake would be to display either as just a vertical line that could either be a "1" or "I". Pay attention to your font!

2. Print the key in the package in a big, bold, readable by people with bad eyesight, font.

3. Put some spaces in the damn thing. Nobody wants to try type in a 25 digit long key without someway of breaking it into chunks the brain can deal with. Thats why 16 digit credit card numbers are printed on the card in 4 groups of 4 digits.

4. When displaying the key as the user types it in, also automatically space the digits out the same way that you've printed as per Rule 3. That way it's easier for the user to keep track of what they are typing in.

5. Don't use upper and lower case as separate digits in the key. Only use upper case, accept keyboard entry of upper or lowercase, but display uppercase on the screen regardless.

6. Always call it by the same name. Don't label it as something like "Product Registration Number" in the packaging and then have the game ask the user to enter his "Serial Key." (Generally, picking one name for something and sticking with it should be a no-brainer for your entire game, but some people need reminding. Not mentioning any names.)