INN Validator (Russia Tax ID)
Validate authenticity, structure, and checksum of Russian INN numbers.
About Russian INN Validation
This tool inspects the 10-digit or 12-digit INN string, verifying length and confirming check digits against official Federal Tax Service formulas.
Real-time client-side validation performed securely in browser memory.
INN Validation Algorithm
- Verify input contains exactly 10 digits (entity) or 12 digits (individual).
- For 10 digits: compute CD using weights [2, 4, 10, 3, 5, 9, 4, 6, 8] and formula (Sum % 11) % 10.
- For 12 digits: compute 1st CD using [7, 2, 4, 10, 3, 5, 9, 4, 6, 8] and 2nd CD using [3, 7, 2, 4, 10, 3, 5, 9, 4, 6, 8].
- Compare with final check digits.