Singapore NRIC / FIN Validator
Validate the authenticity, format, and checksum of Singapore NRIC / FIN.
About Singapore NRIC / FIN Validation
The NRIC (National Registration Identity Card) and FIN (Foreign Identification Number) are the unique 9-character identifiers for Singapore citizens and foreign pass holders.
Structured as 9 characters: leading letter (S=pre-2000 citizens, T=post-2000, F/G/M=foreigners), 7 digits, and a checksum letter calculated via weighted sum [2, 7, 6, 5, 4, 3, 2] Modulo 11.
Anatomy & Structure of NRIC / FIN — Singapore
The Singapore Identity Card number consists of 9 characters in 3 parts:
| Position | Field | Length | Meaning & Rule | Example |
|---|---|---|---|---|
| 1 | Category Prefix | 1 letter | S/T=Citizen/PR (S<2000, T>=2000); F/G/M=Foreigner/FIN (F<2000, G>=2000, M>=2022) | S |
| 2 to 8 | Registration Number | 7 digits | Sequential number issued by Immigration & Checkpoints Authority (ICA) | 1234567 |
| 9 | Check Letter | 1 letter | Calculated via **Weighted Modulo 11** with prefix offset and official tables | D |
Official Algorithm (Weighted Modulo 11 with Offset — ICA Singapore)
Official check letter calculation for NRIC/FIN:
S = offset + Σ (d[i] * W[i]); R = S mod 11; Letter = table[R]
- 1. Multiply the 7 digits by weights: W = [2, 7, 6, 5, 4, 3, 2].
- 2. Add prefix offset: S/F = 0, T/G = 4, M = 3.
- 3. Compute total sum and remainder R = S mod 11.
- 4. Map R to check letter using official ICA tables (S/T, F/G, or M).