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Pakistani NTN Tax Number Validator

Validate Pakistani National Tax Numbers (NTN) in real time.

Pakistani NTN Validation

Validates the 8-digit structure against official FBR weighted modulo 11 checksum rules.

Ensures accuracy for tax reporting and compliance systems in Pakistan.

Anatomy & Structure of National Tax Number (NTN) — Pakistan

The Pakistani Tax Number consists of 8 characters in 2 parts (1234567-8):

PositionFieldLengthMeaning & RuleExample
1 to 7Taxpayer Sequential Number7 digitsUnique taxpayer sequence assigned by Federal Board of Revenue (FBR)1234567
8Check Digit1 digitCalculated via **Weighted Modulo 11** with weights [8, 7, 6, 5, 4, 3, 2]8

Official Algorithm (Weighted Modulo 11 — FBR Pakistan)

Check digit calculation for Pakistani NTN:

S = Σ d[i] * (8 - i) (i=0..6); R = S mod 11; DV = (R === 0 || R === 1) ? 0 : 11 - R
  1. 1. Multiply the first 7 digits by weights: W = [8, 7, 6, 5, 4, 3, 2].
  2. 2. Sum all weighted products into total S.
  3. 3. Compute remainder R of S divided by 11.
  4. 4. If R is 0 or 1, check digit is 0; otherwise DV = 11 - R.

Frequently Asked Questions