Are these real postal codes?
The sample rows are real ZIP codes, such as 10016 in Manhattan and 94107 in San Francisco. Generated rows start with a real regional prefix and end in random characters, so the shape and region are right while some full codes are unassigned.
Will a generated code pass AVS?
Not on a live card. AVS compares the code with the address the bank holds for the card. In a payment sandbox the result depends on the test card number, so any valid code from this page works there.
What is a billing postal code?
The postal code of the address where the card issuer sends statements. The code often differs from the shipping code, which is why checkout forms ask for both.
Why do some codes start with 0?
ZIPs across New England, New Jersey, and Puerto Rico start with 0, as do Northern Territory postcodes, Dresden and Leipzig PLZ codes, and Sapporo codes. They are the best rows for catching fields stored as numbers.
What does the pattern checker test?
Shape only. The checker runs the regex for the selected country against your pasted code, after trimming spaces at each end. A pass means the format is right, not the code assigned.
How many codes per click?
Up to 25. Valid mode never repeats a code inside one batch. Invalid mode cycles through every rule for the country before repeating one.