Australia TFN Validator
Online Australian Tax File Number validator. Excellent for your tests.
How does TFN validation work?
The validator checks if the document has exactly 9 numeric digits, applies positional weights [1, 4, 3, 7, 5, 8, 6, 9, 10] by multiplying each corresponding digit, and sums the total.
If the total sum is divisible by 11 (remainder of zero), the TFN is considered valid. Otherwise, the number is invalid.