Unified validation, parsing, and formatting of 250+ standard identifier numbers for Clojure - IBAN/BIC, credit cards, ISBN/ISSN/ISIN, and national ID, VAT/GST, and tax numbers for 80+ countries - behind one small API.
Unofficial, community-maintained. Not affiliated with Apache, iban4j, or any card network.
Clojure has plenty of one-identifier libraries (an IBAN parser here, a Luhn checker there),
most of them tiny and unmaintained, each with its own API. There was no single library that
validates the common, checksummable identifiers under one consistent interface - the way
Python's python-stdnum does. stdnum-clj is that
facade, and now covers python-stdnum's full catalogue of number formats. For the international
identifiers it
wraps the maintained Apache Commons Validator
and iban4j engines rather than reinventing them, so
those checks are as correct as those libraries and stay correct as they're updated. The national
and tax standards with public, well-documented algorithms are implemented clean-room and kept
under this library's EPL license.
Leiningen / Boot:
[net.clojars.savya/stdnum-clj "0.30.0"]deps.edn:
net.clojars.savya/stdnum-clj {:mvn/version "0.30.0"}(require '[stdnum.core :as stdnum])
;; valid? - dispatch on an identifier-type keyword (any of `stdnum/types`)
(stdnum/valid? :iban "GB82 WEST 1234 5698 7654 32") ;=> true
(stdnum/valid? :credit-card "4111 1111 1111 1111") ;=> true (separators tolerated)
(stdnum/valid? :de-vat "DE136695976") ;=> true (country prefix optional)
(stdnum/valid? :iban "GB82 WEST 1234 5698 7654 33") ;=> false (bad check digit)
;; parse - validity plus extracted fields where they exist
(stdnum/parse :credit-card "378282246310005") ;=> {:valid? true, :network :amex, :iin "378282", :last4 "0005"}
(stdnum/parse :iban "GB82WEST12345698765432")
;=> {:valid? true, :country "GB", :bban "WEST12345698765432",
; :bank-code "WEST", :branch-code "123456", :account-number "98765432", :formatted "GB82 WEST ..."}
;; some national IDs embed structured data - parse pulls it out
(stdnum/parse :mx-curp "HEGG560427MVZRRL04")
;=> {:valid? true, :birth-date "1956-04-27", :gender :female, :state "VZ", :state-name "Veracruz"}
(stdnum/parse :za-id "8001015009087")
;=> {:valid? true, :gender :male, :citizen true, :birth-date "1980-01-01"}
;; format - canonical human form, or nil if invalid
(stdnum/format :br-cnpj "11222333000181") ;=> "11.222.333/0001-81"
;; detect - which types consider a value valid
(stdnum/detect "4111111111111111") ;=> [:credit-card :luhn]
;; helpers
(stdnum/card-network "6011111111111117") ;=> :discover
stdnum/types ;=> #{:iban :credit-card :de-vat ...} (the full set)valid?, parse, and format throw IllegalArgumentException only on an unknown
identifier type (a programming bug). Bad data never throws: valid? returns false,
parse returns {:valid? false}, format returns nil.
When you need the raw algorithm rather than a typed validator, stdnum.checkdigit exposes them
directly:
(require '[stdnum.checkdigit :as cd])
(cd/luhn-valid? "79927398713") ;=> true
(cd/luhn-check-digit "7992739871") ;=> "3"
(cd/verhoeff-check-digit "23412341234") ;=> "6"
(cd/iso7064-mod11-2-check "000000021825009") ;=> "7" (ORCID/ISNI check char, may be "X")
(cd/iso7064-mod97-10-valid? "5493001KJTIIGC8Y1R12") ;=> true (LEI / IBAN family)stdnum.gs1-128 decodes GS1-128 (UCC/EAN-128) Application Identifier element strings - the data
carried on logistics and retail barcodes - in either the parenthesized or raw FNC1 form:
(require '[stdnum.gs1-128 :as gs1])
(gs1/parse "(01)09521234543213(3103)000123(10)ABC123")
;=> [{:ai "01" :label "GTIN" :value "09521234543213"}
; {:ai "3103" :label "NET WEIGHT (kg)" :value "000123" :decimals 3 :decimal-value 0.123}
; {:ai "10" :label "BATCH/LOT" :value "ABC123"}]
(gs1/parse-map "(01)09521234543213(10)ABC123") ;=> {"01" "09521234543213", "10" "ABC123"}A checksum proves a VAT number is well-formed; it can't prove the company exists. stdnum.vies
checks a number against the EU's live VIES registry:
(require '[stdnum.vies :as vies])
(vies/check "LU26375245")
;=> {:valid? true, :country "LU", :vat-number "26375245",
; :name "AMAZON EUROPE CORE S.A R.L.", :address "38, AVENUE JOHN F. KENNEDY...", ...}A member-state outage (MS_UNAVAILABLE, rate-limiting, …) returns {:error "..."} rather than a
misleading :valid? false - validity is genuinely unknown when the registry can't answer. This is
the only part of the library that does network I/O; it lives in its own namespace, requires JDK
11+ (uses java.net.http), and pulls in org.clojure/data.json. stdnum.core stays pure.
stdnum/types is the authoritative set. National identifiers are keyed by an ISO-3166 prefix
(:br-cpf, :us-ssn, :de-vat); full descriptions are on cljdoc.
All 257 types, by category
| Category | Types |
|---|---|
| Banking & cards | :credit-card (+ network) · :iban · :bic · :aba · :mx-clabe · :cz-bankaccount · :nz-bankaccount · :iso11649 · :ar-cbu · :es-ccc · :be-ogm · :ch-esr · :no-kontonr · :eu-at02 |
| Securities | :isin · :lei · :cusip · :sedol · :de-wkn · :figi · :cfi |
| Publishing / media / device | :isbn · :issn · :ismn · :iswc · :grid · :isan · :eu-banknote · :imei · :luhn · :isrc · :isil · :mac · :imsi · :meid · :bitcoin |
| Commerce / logistics / vehicle / industry | :ean13 · :ean8 · :upc · :gtin14 · :sscc · :gln · :iso6346 · :upu-s10 · :vin · :imo · :cas · :nhs · :npi · :it-aic · :eu-eic · :eu-ecnumber · :eu-excise · :eu-nace · :es-cae · :es-cups · :es-postalcode · :at-postleitzahl · :nl-brin · :nl-postcode · :se-postnummer |
| Research / name | :orcid · :isni |
| National & tax IDs — Europe | :gb-nino · :es-dni · :es-nie · :es-nif · :es-referenciacatastral · :nl-bsn · :nl-identiteitskaartnummer · :nl-onderwijsnummer · :se-pnr · :no-org · :no-fodselsnummer · :pt-nif · :pt-cc · :cz-ico · :hr-oib · :it-cf · :ch-uid · :ch-ahv · :be-nn · :be-bis · :be-ssn · :be-eid · :fi-hetu · :fr-nir · :fr-nif · :fr-accise · :pl-pesel · :ie-pps · :ee-ik · :lt-asmens · :si-emso · :ro-cnp · :ro-cf · :ro-cui · :ro-onrc · :cz-rc · :sk-rc · :gr-amka · :bg-egn · :bg-pnf · :ru-inn · :ru-snils · :ua-edrpou · :ua-rntrc · :is-kennitala · :ru-ogrn · :rs-pib · :me-pib · :mk-edb · :pl-regon · :sk-ico · :ee-rk · :fr-siren · :fr-siret · :fr-rcs · :se-orgnr · :es-cif · :md-idno · :by-unp · :si-maticna · :ad-nrt · :al-nipt · :li-peid · :sm-coe · :gb-utr · :gb-upn · :dk-cvr · :dk-cpr · :fi-ytunnus · :fi-associationid · :fi-veronumero · :de-idnr · :de-handelsregisternummer · :de-leitweg · :de-stnr · :az-voen · :at-businessid · :at-tin · :at-vnr · :jmbg |
| National & tax IDs — Americas | :us-ssn · :us-ein · :br-cpf · :br-cnpj · :ca-sin · :ca-bcphn · :ar-cuit · :ar-dni · :cl-rut · :co-nit · :pe-ruc · :pe-cui · :cr-cpf · :cr-cpj · :cr-cr · :ec-ced · :mx-curp · :ve-rif · :do-rnc · :do-cedula · :do-ncf · :uy-rut · :ec-ruc · :py-ruc · :gt-nit · :mx-rfc · :ca-bn · :cu-ni · :sv-nit · :us-itin · :us-atin · :us-ptin · :us-tin |
| National & tax IDs — Asia-Pacific | :au-abn · :au-tfn · :in-pan · :in-aadhaar · :in-epic · :in-vid · :cn-ric · :jp-cn · :jp-in · :nz-ird · :sg-nric · :sg-uen · :hk-id · :kr-brn · :kr-rrn · :tw-gui · :cn-usci · :vn-mst · :au-acn · :nz-nzbn · :id-npwp · :id-nik · :th-moa · :th-pin · :th-tin · :kz-bin · :my-nric · :pk-cnic |
| National & tax IDs — Africa & M. East | :za-id · :za-tin · :tr-tc · :il-idnr · :il-company · :tr-vkn · :mu-nid · :mz-nuit · :ke-pin · :dz-nif · :eg-tn · :gh-tin · :gn-nifp · :ma-ice · :tn-mf · :sn-ninea |
| VAT / GST (EU-27 complete) | :de-vat · :fr-vat · :mc-tva · :it-vat · :be-vat · :pl-vat · :gb-vat · :at-vat · :dk-vat · :fi-vat · :se-vat · :gr-vat · :lu-vat · :si-vat · :ee-vat · :hu-vat · :mt-vat · :sk-vat · :lt-vat · :cy-vat · :ro-vat · :es-vat · :ie-vat · :nl-vat · :lv-vat · :bg-vat · :hr-vat · :cz-vat · :pt-vat · :in-gstin · :eu-oss · :ch-vat · :no-mva · :fo-vn · :is-vsk · :vatin · :eu-vat |
International identifiers are wrapped from Commons Validator / iban4j; global and national standards with public, well-documented algorithms (LEI, VAT, CPF/CNPJ, SSN, …) are implemented clean-room and stay under this library's EPL license. More are added on demand - open an issue for an identifier you need.
Correctness is pinned by a cited corpus, not ad-hoc assertions. test/stdnum/vectors.edn maps
every one of the identifier types to {:valid [...] :invalid [...] :source "..."}, and :source
is mandatory. Each vector is a worked example from the standard, a government registry, an issuing
company's published number, a python-stdnum module
doctest, or a live VIES check. The test suite is driven from this file, so adding a format means
adding a cited vector first.
Every checksummed type is verified against an independently recomputed check digit. Where a type is
purely structural (validated by format, embedded date, or component code, with no check digit) the
:source says so. Where no published example exists, a number constructed from the published
algorithm is cited as constructed rather than passed off as a real published number.
For EU VAT, entries tagged :vies true are confirmed live-registered companies, and
lein test :integration re-checks them against the official VIES service. (A useful distinction
that surfaced: a valid checksum doesn't imply a registered number - several common example VAT
numbers are checksum-valid but unregistered, and are labelled as algorithm examples accordingly.)
Copyright © 2026 Savyasachi
Distributed under the Eclipse Public License 2.0.