ISIN validator plus CUSIP, SEDOL and FIGI check-digit validation; builds an ISIN from an NSIN
ISIN validator plus CUSIP, SEDOL and FIGI check digits: validate the check digit of a financial security identifier (ISIN per ISO 6166). Returns the verdict, the computed correct check character, and for an ISIN the issuing country prefix and the embedded NSIN. Also builds an ISIN from a country code plus a 9-character NSIN. Format and checksum only, no security master lookup.
Output (data): validate: valid, type (isin|cusip|sedol|figi|unknown), normalised, check_char (string|null, null when the type is unknown), check_char_ok, country (ISIN only; string|null), nsin (ISIN only; string|null), reason (string|null, null when valid), algorithm (string|null, null when the type is unknown). build-isin: isin plus the same fields.
Deterministic: identical input returns identical output, so the response is served with Cache-Control: private, max-age=31536000, immutable (the paying client may cache it indefinitely; shared caches must not, because the response is paid).
Price: $0.05 USDC per call (x402, Base). Route contract version 1.0.0. Docs: https://api.duoleads.com/docs#id-security
Request
- Base URL: https://api.duoleads.com
- URL: https://api.duoleads.com/v1/id/security
- Auth: none declared
Query parameters
validate (default) or build-isin. Accepted: validate, build-isin.
ISIN, CUSIP, SEDOL or FIGI to validate. Required when op=validate. Accepted: an alphanumeric security identifier of at most 24 characters.
ISO 3166-1 alpha-2 code or XS. Required when op=build-isin. Accepted: at most 16 characters.
Exactly 9 alphanumeric characters. Required when op=build-isin. Accepted: exactly 9 alphanumeric characters.
Response
Paid and settled. data is route-specific; a route that judges its input returns 200 with data.valid: false for a bad value.
Changes
No recorded changes to this operation across all 1 revision of this API.