# IBAN DK Validator (Mod-97, Length 18)

> IBAN DK Validator (Mod-97, Length 18) is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.004/call, status unknown (last checked 2026-10-02).

Validates whether a given IBAN string is a mod-97-valid Danish (DK) IBAN of exactly 18 characters

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/check-iban-dk?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/iban-dk-validator-mod-97-length-18-f7284b1a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_b1KUVrlr6ObjNkb5782BC

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability iban-dk-validator-mod-97-length-18-f7284b1a -d '<json body>'
```

Example prompt: Can you check if this IBAN is a valid Danish bank account number — it should be 18 characters and pass the mod-97 check: DK5000400440116243?

## When to prefer this

Use this endpoint when you specifically need to validate a Danish (DK) IBAN for correctness — both the exact 18-character length and the mod-97 checksum. Prefer the free sandbox POST /v1/sandbox/check-iban-dk first to avoid the $0.004 USDC charge. Do not use this for IBANs from other countries; choose a country-agnostic IBAN validator for non-DK bank numbers.

## Known failure modes

- IBAN is not DK-prefixed — endpoint only validates Danish IBANs
- IBAN length is not 18 characters — fails length check
- Mod-97 checksum fails — IBAN is structurally invalid
- Input string is empty or exceeds schema limits — rejected by input validation
- Malformed input (non-string value) causes schema validation error

## How this service works

Call when an agent needs whether an IBAN is a mod-97-valid DK number of length 18. Exact $0.004 USDC. Prefer unpaid POST /v1/sandbox/check-iban-dk first.

## Output

Returns a boolean or structured result indicating whether the provided IBAN string is a valid Danish (DK-prefixed) IBAN: exactly 18 characters long and passing the ISO 7064 mod-97 checksum algorithm.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "description": "JSON value for schema-check SKUs. Omit it on string checks such as email or IBAN."
  },
  "value": {
   "type": "string",
   "examples": [
    "DK50AAAA0000000000"
   ],
   "maxLength": 20000,
   "minLength": 1,
   "description": "Value to check. The route description names the format: email, phone, IBAN, postal code, VAT, national id, or similar."
  },
  "schema": {
   "description": "JSON Schema document for schema-check SKUs. Omit it on string checks."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/iban-dk-validator-mod-97-length-18-f7284b1a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)