Duo Data Utilities
api.duoleads.com · 33 paid endpoints · listed 2026-10-27
Expand an RFC 5545 recurrence rule into concrete occurrence timestamps. Accepts an RRULE string with DTSTART, an IANA time zone, and optional EXDATE and RDATE lists, and returns up to 200 occurrences as both local wall-clock times and UTC instants. Supports FREQ, INTERVAL, COUNT, UNTIL, BYDAY, BYMONTHDAY, BYMONTH, BYSETPOS and WKST. Occurrences moved by a DST gap carry gap: true. Rules needing over 50,000 candidate evaluations are rejected.
livelast check 5 days ago
100%valid x402 answers, 72 h
sharedUSDC received on Base, 7 days
11distinct payers, 7 days
67.7score (0-100)
Paid endpoints
| Method | Endpoint | Price | Networks |
|---|---|---|---|
| GET | api.duoleads.com/v1/chain/address Identify which blockchain an address belongs to and validate its encoding: EVM EIP-55 checksum, Bitcoin base58check and bech32/bech32m with witness version, Sol | $0.05 | Base |
| GET | api.duoleads.com/v1/chain/selector Compute the Keccak-256 hash of a Solidity function or event signature and derive the 4-byte function selector and the 32-byte event topic. Normalises the signat | $0.05 | Base |
| GET | api.duoleads.com/v1/code/hash 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, plus HMAC with a | $0.05 | Base |
| GET | api.duoleads.com/v1/code/idn Convert internationalised domain names between Unicode and ASCII punycode in either direction, label by label, and validate each label against IDNA2008: length, | $0.05 | Base |
| GET | api.duoleads.com/v1/code/jwt 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 claims — wheth | $0.05 | Base |
| GET | api.duoleads.com/v1/code/semver Parse a semantic version into major, minor, patch, prerelease and build parts; compare two versions by precedence including prerelease ordering; or test whether | $0.05 | Base |
| GET | api.duoleads.com/v1/code/url 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 belong to the | $0.05 | Base |
| GET | api.duoleads.com/v1/geo/distance Distance and direction between WGS-84 coordinates: geodesic distance by Vincenty with a haversine fallback, initial and final bearing, the midpoint, and the des | $0.05 | Base |
| GET | api.duoleads.com/v1/geo/geohash Encode a WGS-84 latitude and longitude to a geohash at a chosen precision, or decode a geohash back to its bounding box, centre point and error bounds in metres | $0.05 | Base |
| GET | api.duoleads.com/v1/geo/pluscode Encode coordinates as an Open Location Code (plus code) at a chosen length, or decode a full code back to its bounding box and centre. Also shortens a full code | $0.05 | Base |
| GET | api.duoleads.com/v1/geo/polygon Geometric predicates on a GeoJSON geometry supplied in the request: point-in-polygon with correct hole handling, bounding box, centroid, signed area in square m | $0.05 | Base |
| GET | api.duoleads.com/v1/id/gs1 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, the computed correct ch | $0.05 | Base |
| GET | api.duoleads.com/v1/id/iban Validate an IBAN: length for its country, permitted character classes per field, and the ISO 7064 mod-97-10 check digits. Returns the verdict with a specific fa | $0.05 | Base |
| GET | api.duoleads.com/v1/id/iban-build Construct an IBAN from a country code and the domestic account parts, computing the ISO 7064 mod-97-10 check digits. Takes either a single BBAN string or named | $0.05 | Base |
| GET | api.duoleads.com/v1/id/national Validate a national identity, tax or company registration number against its country's official checksum rule. Covers 23 countries including NL BSN, ES NIF/NIE/ | $0.05 | Base |
| GET | api.duoleads.com/v1/id/security Validate the check digit of a financial security identifier: ISIN (ISO 6166), CUSIP, SEDOL and FIGI. Returns the verdict, the computed correct check character, | $0.05 | Base |
| GET | api.duoleads.com/v1/num/allocate 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 distributed one mi | $0.05 | Base |
| GET | api.duoleads.com/v1/num/radix Convert an integer between any two numeric bases from 2 to 36, with arbitrary precision so values far beyond 2^53 are exact. Accepts an optional sign and common | $0.05 | Base |
| GET | api.duoleads.com/v1/num/stats Descriptive statistics for a supplied numeric array in one call: count, sum, mean, median, mode, variance and standard deviation with variance and standard devi | $0.05 | Base |
| GET | api.duoleads.com/v1/num/words Spell a number out in words in English, Dutch, German, French, Spanish, Italian, Portuguese, Polish, Russian, Turkish, Swedish or Japanese, in cardinal, currenc | $0.05 | Base |
| GET | api.duoleads.com/v1/ref/airport Look up an airport by IATA or ICAO code and get its name, city, country, ISO 3166-2 region code, WGS-84 coordinates and elevation, or find the nearest airports | $0.05 | Base |
| GET | api.duoleads.com/v1/ref/country Look up a country or territory by ISO 3166-1 alpha-2, alpha-3 or numeric code, or by name, and get the other codes, the English name, the UN M49 region and sub- | $0.05 | Base |
| GET | api.duoleads.com/v1/ref/currency Look up a currency by ISO 4217 code: its alphabetic and numeric codes, English name, minor-unit exponent, the smallest cash denomination where it differs from t | $0.05 | Base |
| GET | api.duoleads.com/v1/ref/nuts Look up a NUTS statistical region of the European Union: resolve a NUTS code to its name, country and level, walk up to its parents or down to its children, or | $0.05 | Base |
| GET | api.duoleads.com/v1/text/similarity Compare two strings and return every standard similarity measure in one call: Levenshtein and Damerau-Levenshtein edit distance, normalised similarity, Jaro and | $0.05 | Base |
| GET | api.duoleads.com/v1/text/slug Turn arbitrary text into a URL-safe slug. Decomposes accents, transliterates German umlauts, Scandinavian and Turkish letters, and the ligatures that lose meani | $0.05 | Base |
| GET | api.duoleads.com/v1/text/transliterate Transliterate Cyrillic text into Latin using a named standard: ISO 9:1995 (one-to-one, with diacritics) or the BGN/PCGN Russian system. Returns the transliterat | $0.05 | Base |
| GET | api.duoleads.com/v1/text/unicode Analyse a string at the Unicode level: apply NFC, NFD, NFKC or NFKD normalisation, report which normalisation forms it is already in, list the scripts present, | $0.05 | Base |
| GET | api.duoleads.com/v1/time/business-days Business-day arithmetic with a caller-supplied calendar: add or subtract N working days from a date, or count the working days between two dates. The weekend is | $0.05 | Base |
| GET | api.duoleads.com/v1/time/calendar Convert a Gregorian date to other calendar systems and back: Islamic (both the tabular civil calendar and the Umm al-Qura variant), Hebrew, Japanese imperial er | $0.05 | Base |
| GET | api.duoleads.com/v1/time/dst List the daylight-saving transitions for an IANA time zone over a date range: the exact instant of each shift, the offset before and after, and whether local cl | $0.05 | Base |
| GET | api.duoleads.com/v1/time/rrule Expand an RFC 5545 recurrence rule into concrete occurrence timestamps. Accepts an RRULE string with DTSTART, an IANA time zone, and optional EXDATE and RDATE l | $0.05 | Base |
| GET | api.duoleads.com/v1/time/zone 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 and time, the UTC off | $0.05 | Base |
Latest checks
| When | Endpoint | HTTP | ms | Result |
|---|---|---|---|---|
| 5 days ago | api.duoleads.com/v1/chain/address | 402 | 684 | valid x402 v2 terms |
Income on Base (7 days)
This provider's payout address is shared by several providers, so its income is not shown as its own.
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x402_provider_claim (sign with your payout address), and get an alert within minutes when it stops answering with x402_monitor_create ($5 for 30 days). Both work over MCP (https://logicnodes.io/mcp/v2) or POST https://logicnodes.io/v1/tools/<tool>.Income is all USDC received by the provider's payout address on Base, whatever the source. Score: 0-100: 50 x share of checks in the last 72 h that returned valid x402 payment terms + 30 x min(1, log10(1 + USDC received in 7 days) / 4) + 20 x min(1, log10(1 + distinct payers in 7 days) / 3). A provider never checked scores on income only; income is all USDC received by its payout address on Base, whatever the source. JSON: /v1/observatory/providers/api.duoleads.com