TFN Validator
Check Tax File Number format using ATO weighting rules for 8 and 9 digit TFNs.
TOOL Private Local Check
TFNs are private — this tool does not store or transmit your TFN.
Never share your TFN with unverified parties.
How to use TFN Validator
1
Enter TFN
Paste your 8 or 9 digit TFN.
2
Validate
Run format check based on ATO weighting.
3
Review result
See valid or invalid TFN format.