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Validate a national identity, tax or company registration number against its country's official checksum rule.

Validate and convert GS1 identifiers: GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), GTIN-14, GLN and SSCC.

Validate the check digit of a financial security identifier: ISIN (ISO 6166), CUSIP, SEDOL and FIGI.

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.

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 clocks jump forward or back.

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.

Expand an RFC 5545 recurrence rule into concrete occurrence timestamps.

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 era, Republic of China, Buddhist and Persian.

Turn arbitrary text into a URL-safe slug.

Transliterate Cyrillic text into Latin using a named standard: ISO 9:1995 (one-to-one, with diacritics) or the BGN/PCGN Russian system.

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, and flag confusable and homoglyph characters — Cyrillic а in a Latin word, zero-width joiners, bidirectional overrides, invisible characters.

Compare two strings and return every standard similarity measure in one call: Levenshtein and Damerau-Levenshtein edit distance, normalised similarity, Jaro and Jaro-Winkler, longest common subsequence, Dice coefficient on character bigrams, and the Soundex, Metaphone and NYSIIS phonetic keys of each string.

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 same owner.

Convert internationalised domain names between Unicode and ASCII punycode in either direction, label by label, and validate each label against IDNA2008: length, leading and trailing hyphens, the hyphen-hyphen rule at positions 3 and 4, disallowed code points and bidirectional rules.

Parse a semantic version into major, minor, patch, prerelease and build parts; compare two versions by precedence including prerelease ordering; or test whether a version satisfies a range expression using caret, tilde, hyphen, x-ranges and comparator sets.

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 any of them.

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 — whether exp has passed, whether nbf is in the future, and the remaining lifetime in seconds against a supplied or current instant.

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.

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.

Geometric predicates on a GeoJSON geometry supplied in the request: point-in-polygon with correct hole handling, bounding box, centroid, signed area in square metres, perimeter length, and ring winding order.

Distance and direction between WGS-84 coordinates: geodesic distance by Vincenty with a haversine fallback, initial and final bearing, the midpoint, and the destination point reached from a start point on a given bearing and distance.

Identify which blockchain an address belongs to and validate its encoding: EVM EIP-55 checksum, Bitcoin base58check and bech32/bech32m with witness version, Solana base58 and on-curve check, Cosmos bech32 with its HRP, Tron, XRP, Litecoin, Dogecoin, Cardano, Polkadot SS58 and Algorand.

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.

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 search regions by name.

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 to a coordinate within a radius.

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 the minor unit, and the territories that use it.

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-region, the currencies in use, and the country-code top-level domain.

Convert an integer between any two numeric bases from 2 to 36, with arbitrary precision so values far beyond 2^53 are exact.

Spell a number out in words in English, Dutch, German, French, Spanish, Italian, Portuguese, Polish, Russian, Turkish, Swedish or Japanese, in cardinal, currency or year form, and ordinal form in English, Dutch, German and French.

Descriptive statistics for a supplied numeric array in one call: count, sum, mean, median, mode, variance and standard deviation with variance and standard deviation honouring ddof (default 1, the sample form; 0 gives the population form) and always-population *_population fields, min, max, range, the quartiles and interquartile range, skewness, kurtosis, and any requested percentiles.

Split a money amount into shares without losing or inventing a cent.