U.S. passport number validation rules
A U.S. passport number has no publicly known checksum, so the rule implemented here is one explicit check: exactly 9 characters, all digits, no letters; this page walks through that rule step by step with concrete numbers, and is upfront that it is the convention this tool adopted, not a universal standard.
Any character outside 0 through 9 fails immediately under this convention, with no exception for the leading position or any other.
The `/^\d{9}$/` regex requires exactly 9 positions; seven digits fall short of the minimum and maximum this rule allows.
Length and character class both match, so this value clears the single check the tool implements for this document.
There is no simple public checksum to validate issuance from the number alone.
No. The only check is the `/^\d{9}$/` regex, with no modulus arithmetic or positional weighting; that differs from the CNH and PIS/PASEP in the same kit, which do compute a real check digit.
Because the convention adopted here is purely numeric: `isValidUsPassportFormat` only accepts 9 digits, so any letter, in any position, fails immediately.
Not necessarily for every booklet, since the format has changed over time and includes versions with a leading letter; 9 digits is the convention this tool standardized on to cover the most common test case.
The EIN and ITIN check a prefix or group range against an official IRS table; passport validation here checks only length and character class, with no reference table involved.
Generation happens locally in the browser. Analytics receives only action, status, type and format, never the generated passport number.