Hello all…. I have been given a number of gift vouchers for my birthday (lucky me!)….. They are in the form of a 7 digit alphanumeric code. For example:

273813a

Now there does not seem to be anything else needed and they last a year.

What’s to stop some turnip from guessing and getting lucky with some kind of code generator and stealing my voucher! I know that probability is low of guessing but without knowing how the numbers are generated (digit increments or randomised etc) slightly wary of letting them sit for any length of time…

Overly cautious? Nothing to worry about? Or buy something quick!

Cheers

I’d be more worried about the retailer going bust before you have spent them than the code not working*

* Depending on retailer

Yeah good Point…but this is a big big retailer. Unlikely to go bust (compared to others).

I’d be more worried about them getting stolen from your email than guessed. Alphanumeric so hex based, 7 characters hmmm that gives what 20922789888000 possible codes.

Checksums.

The code will be generated by an algorithm, not sequentially generated. A valid code has to match that algorithm.

Alphanumeric so hex based

Could be truly alphanumeric rather than hex. 36^7 =78,364,164,096 possible codes. (One of us has their maths wrong, hex would be 268 million, no?)

Probably mine. I’m very tired (baby). I also copy pasted the number instead of calculating, page 1 error.

For example:

273813a

Brilliant – free money. Just have to figure out where to spend it

this is a big big retailer.

CRC > Checkout > 273813a.
No

Wiggle> Checkout > 273813a.
No

Amazon> Checkout > 273813a.
No

eBay> Checkout > 273813a.
No

Bangaholic > Checkout > 273813a.
BINGO!

😀 very good