# Duo Data Utilities

> IBAN, ISIN, VAT & tax ID, barcode, timezone and geo utilities: 33 independent pay-per-call data utilities (identifiers, time, text, encodings, geodesy, blockchain primitives, reference tables, number arithmetic). $0.05 per call, payable over x402 (USDC on Base, eip155:8453). No account, no API key. A2A: JSON-RPC at https://api.duoleads.com/a2a; send a DataPart {"skill": "<skill id>", "params": {...}}; skill execution is paid through the a2a-x402 extension. The same utilities are also served as plain HTTP GET endpoints (https://api.duoleads.com/openapi.json) and as MCP tools over Streamable HTTP at https://api.duoleads.com/mcp (tools/list free, tools/call paid).

- **Domain**: `api.duoleads.com`
- **Provider**: Duo Leads (https://api.duoleads.com)
- **A2A protocol version**: 1.0
- **Kind**: paid_api
- **Category**: data
- **Live-responds (last probe)**: True
- **Signed card**: False
- **Streaming**: False
- **Quality score**: 100%
- **Payment protocol**: a2a_x402
- **Wallet**: `0xcd673f7e1dad254347aeab6be0defe8b9c6b3a39`

## Skills
- **VAT, tax ID and national ID validator: 23 countries, checksum only (VAT formats BE, DE, FR, IT, PL, AT, CH, IE)** — VAT, tax ID and national ID validator: check a national identity, tax or company registration number against its country's official checksum rule. Covers 23 cou
- **GTIN barcode validator: EAN-13, UPC-A (GTIN-12), GTIN-8/14, GLN and SSCC check digits** — GTIN barcode validator: validate and convert GS1 identifiers: GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), GTIN-14, GLN and SSCC. Returns the check-digit verdict,
- **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, th
- **IBAN validator: length, mod-97 check digits, bank/branch/account breakdown (89 countries)** — IBAN validator: validate an IBAN's length for its country, permitted character classes per field, and the ISO 7064 mod-97-10 check digits. Returns the verdict w
- **IBAN generator: build an IBAN from country and BBAN or bank/branch/account, computing check digits** — IBAN generator: construct an IBAN from a country code and the domestic account parts, computing the ISO 7064 mod-97-10 check digits. Takes a single BBAN string 
- **Timezone converter: instant to local time in an IANA time zone and back, with UTC offset and DST state** — Timezone converter: convert an instant to wall-clock time in a named IANA time zone, or a wall-clock time in a zone back to an instant. Returns the local date a
- **DST transitions: next daylight-saving time changes for an IANA time zone** — DST transitions: list the daylight-saving time changes for an IANA time zone over a date range: the exact instant of each shift, the offset before and after, an
- **Business days calculator: add or count working days with your weekend mask and holiday list** — Business days calculator with a caller-supplied calendar: add or subtract N working days from a date, or count the working days between two dates. The weekend i
- **RRULE expander: RFC 5545 recurrence rule to concrete occurrence dates** — RRULE expander: expand an RFC 5545 recurrence rule into concrete occurrence timestamps. Accepts an RRULE string with DTSTART, an IANA time zone, and optional EX
- **Calendar converter: Gregorian to Hijri, Hebrew, Japanese era, Persian and more, plus Easter date** — Calendar converter: convert a Gregorian date to other calendar systems: Islamic (both the tabular civil calendar and the Umm al-Qura variant), Hebrew, Japanese 
- **Slug generator: Unicode-aware URL slug with transliteration** — Slug generator: turn arbitrary text into a URL-safe slug. Decomposes accents, transliterates German umlauts, Scandinavian and Turkish letters, the ligatures tha
- **Cyrillic transliteration to Latin (ISO 9:1995, BGN/PCGN Russian)** — Cyrillic transliteration to Latin using a named standard: ISO 9:1995 (one-to-one, with diacritics, covering the full standard: Russian, other Slavic, historic a
- **Unicode normalization (NFC/NFKC), script detection and homoglyph/confusable check** — Unicode normalization and confusables check: apply NFC, NFD, NFKC or NFKD, report which forms a string is already in, list the scripts present (all Unicode scri
- **String similarity: Levenshtein, Jaro-Winkler distance and Soundex/Metaphone phonetic keys** — String similarity: compare two strings and return every standard measure in one call: Levenshtein and Damerau-Levenshtein edit distance, normalised similarity, 
- **URL parser: parse, canonicalize and extract the registrable domain (eTLD+1)** — URL parser: parse and canonicalise a URL, and extract its registrable domain using the Public Suffix List — the part an agent needs to decide whether two URLs b
- **Punycode converter: IDN domain to ASCII and back, with IDNA2008 label validation** — Punycode converter: convert internationalised domain names between Unicode and ASCII punycode in either direction, label by label, and validate each label again
- **Semver parser: parse and compare versions, check range satisfaction** — Semver parser and comparator: parse a semantic version into major, minor, patch, prerelease and build parts; compare two versions by precedence including prerel
- **Hash generator: SHA-256, SHA-512, SHA-3, Keccak-256, BLAKE2 and HMAC digests** — Hash generator: compute a cryptographic digest of supplied data: SHA-256, SHA-384, SHA-512, SHA-1, SHA3-256, SHA3-512, Keccak-256, BLAKE2b-256 and BLAKE2b-512, 
- **JWT decoder: header, claims and expiry state (no signature verification)** — JWT decoder: decode a JSON Web Token without verifying it: returns the header, the claims, the signature length and algorithm, and a computed view of the time c
- **Geohash encoder and decoder with neighbour cells** — Geohash encoder and decoder: encode a WGS-84 latitude and longitude to a geohash at a chosen precision, or decode a geohash back to its bounding box, centre poi
- **Plus code (Open Location Code) encoder and decoder** — Plus code (Open Location Code) encoder and decoder: encode coordinates as a plus code at a chosen length, or decode a full code back to its bounding box and cen
- **Point in polygon check, plus bounding box, centroid and area for GeoJSON** — Point in polygon check and GeoJSON geometry: point-in-polygon with correct hole handling, bounding box, centroid, signed area in square metres, perimeter length
- **Distance calculator: geodesic distance, bearing and destination point on WGS-84** — Distance calculator: distance and direction between WGS-84 coordinates: geodesic distance by Vincenty with a haversine fallback, initial and final bearing, the 
- **Crypto address validator: detect the blockchain and verify the checksum (EVM, Bitcoin, Solana and more)** — Crypto address validator: identify which blockchain an address belongs to and validate its encoding: EVM EIP-55 checksum, Bitcoin base58check and bech32/bech32m
- **Solidity function selector: Keccak-256, 4-byte selector and event topic from a signature** — Solidity function selector and event topic: compute the Keccak-256 hash of a function or event signature and derive the 4-byte selector and the 32-byte topic. N
- **NUTS region lookup: EU statistical region codes, names and hierarchy** — NUTS region lookup (EU statistical regions): resolve a NUTS code to its name, country and level, walk up to its parents or down to its children, or search regio
- **Airport lookup by IATA or ICAO code: name, coordinates, elevation, time zone; nearest airports** — Airport lookup by IATA or ICAO code: get the airport's name, city, country, ISO 3166-2 region code, WGS-84 coordinates, elevation and IANA time zone, or find th
- **Currency lookup: ISO 4217 codes, names, minor units and cash rounding** — Currency lookup by ISO 4217 alphabetic or numeric code: the official English name, minor-unit exponent, fund flag, the smallest cash denomination where it diffe
- **Country lookup: ISO 3166 codes, currency, TLD, UN region and ISO 3166-2 subdivisions** — Country lookup: find a country or territory by ISO 3166-1 alpha-2, alpha-3 or numeric code, or by name, and get the other codes, the official and common English
- **Base converter: integers between number bases 2 to 36 (hex, binary, octal)** — Base converter: convert an integer between any two numeric bases from 2 to 36 (hex, binary, octal and more), with arbitrary precision so values far beyond 2^53 
- **Number to words in 12 languages, with ordinal and currency forms** — Number to words: spell a number out in English, Dutch, German, French, Spanish, Italian, Portuguese, Polish, Russian, Turkish, Swedish or Japanese, in cardinal,
- **Statistics calculator: mean, median, standard deviation, quartiles and percentiles** — Statistics calculator for a numeric array in one call: count, sum, mean, median, mode, variance and standard deviation honouring ddof (default 1, the sample for
- **Money split: allocate an amount into shares with no rounding loss** — Money split: split a money amount into shares without losing or inventing a cent. Divide evenly into N parts, or by a list of ratios, and the remainder is distr

## URLs
- Agent card: https://api.duoleads.com/.well-known/agent-card.json
- Page (HTML): https://agenstry.com/agents/api.duoleads.com
- Documentation: https://api.duoleads.com/docs