# Sudan (SD) IBAN & Bank Routing Validator
> Instant sub-1ms ISO 13616 MOD-97 checksum validation, BBAN decomposition, and bank routing extraction for Sudan (SD) bank accounts.

- **Canonical URL:** https://stanzaapi.com/tools/iban-validator/country/sudan-sd
- **Governing Standard:** ISO 13616 / ISO 7064 MOD-97-10 (SWIFT & ISO 13616 IBAN Registry)
- **Latency:** <1ms Edge
- **Privacy:** In-memory execution only (zero data stored or logged)

## Technical Overview & Governing Rules
In Sudan, the International Bank Account Number (IBAN) has a fixed length of 18 alphanumeric characters starting with the two-letter ISO 3166-1 alpha-2 country code 'SD', followed by two MOD-97 check digits.

The National Basic Bank Account Number (BBAN) follows the official pattern: 14n. The national bank code is located at BBAN character offset [0:2].

National IBAN transfers in Sudan (SD) are settled in SDG.

Validation computes the ISO 7064 Modulo-97-10 checksum by transposing the first 4 characters to the end, converting letters to numeric digits (A=10, ..., Z=35), and calculating arithmetic integer modulo 97 (must equal 1).

## Specification Matrix
| Attribute | Value | Description |
| --- | --- | --- |
| Country Code | SD | ISO 3166-1 alpha-2 |
| Total IBAN Length | 18 characters | Fixed standard length |
| BBAN Format | 14n | National structure (n=numeric, a=alpha, c=alphanumeric) |
| SEPA Zone | No | SEPA compliance status |
| Currency (ISO 4217) | SDG | National settlement currency |
| Bank Code Position | BBAN Offset 0 (2 chars) | National clearing code |
| Branch Code Position | N/A | Branch identification |

## Standard JSON Response Model
```json
{
  "valid": true,
  "iban": "SD00...",
  "countryCode": "SD",
  "countryName": "Sudan",
  "length": 18,
  "bban": "14n",
  "sepa": false,
  "checksumValid": true,
  "bankCode": "XXXX"
}
```

## Frequently Asked Questions & Edge Cases
### Q: How many characters is an IBAN in Sudan?
**A:** An official IBAN in Sudan (SD) is exactly 18 characters in length. Any shorter or longer value fails ISO 13616 validation.

### Q: Is Sudan part of the SEPA payment network?
**A:** Sudan is not a SEPA participant and relies on SWIFT/BIC wire routing.

### Q: What currency are Sudan IBAN transfers settled in?
**A:** IBAN transfers for Sudan (SD) settle in SDG, the national settlement currency. Cross-border SEPA transfers to Sudan may still be denominated in EUR where both banks support the scheme.

### Q: How is the MOD-97 check digit calculated for SD IBANs?
**A:** The first 4 characters are moved to the end, letters are converted to numbers (A=10 to Z=35), and the resulting number is evaluated with modulo 97 arithmetic. A valid IBAN yields a remainder of exactly 1.