@stll/stdnum

Validate, compact, format, generate, and parse standard identifiers through a single Rust implementation. The npm package uses a native N-API binding on Node.js and Bun; @stll/stdnum-wasm serves browsers and edge runtimes, and the same registry is available from Python as stella-stdnum.

This package covers 11 global identifiers and 96 countries through 176 per-module entry points.

Install

npm install @stll/stdnum
# or
bun add @stll/stdnum

For browser or edge runtimes, install both packages:

npm install @stll/stdnum @stll/stdnum-wasm

For Python 3.11 or newer:

pip install stella-stdnum

Usage

import { cz } from "@stll/stdnum";

cz.ico.validate("25596641");
// { valid: true, compact: "25596641" }

cz.ico.validate("12345678");
// { valid: false, error: { code: "INVALID_CHECKSUM", ... } }

cz.rc.format("7103192745");
// "710319/2745"

cz.ico.validateMany(["25596641", "12345678"]);
// [{ valid: true, compact: "25596641" }, { valid: false, error: ... }]

Tree-shaking

Import only what you need:

import ico from "@stll/stdnum/cz/ico";
import iban from "@stll/stdnum/iban";

ico.validate("25596641");
iban.validate("CZ65 0800 0000 1920 0014 5399");

Browser and edge runtimes

Initialize the WebAssembly runtime once before calling the synchronous validator subpaths:

import { initialize } from "@stll/stdnum/browser";
import ico from "@stll/stdnum/cz/ico";

await initialize();
ico.validate("25596641");

Concurrent calls to initialize() share the same promise. Calling a validator before initialization throws StdnumNotInitializedError from @stll/stdnum/browser.

The WASM package also exposes the registry API asynchronously:

import { validate } from "@stll/stdnum-wasm";

await validate("cz.ico", "25596641");

Python

import stella_stdnum

result = stella_stdnum.validate("cz.ico", "25596641")
assert result.valid
assert result.compact == "25596641"

results = stella_stdnum.validate_many("cz.ico", ["25596641", "12345678"])
assert [result.valid for result in results] == [True, False]

The Rust registry owns validator behavior and metadata. TypeScript subpaths, catalog files, and exact TypeScript/Python registry types are generated from that registry. One committed fixture set checks the Rust, Node.js, WASM, and Python surfaces, and ty checks the installed Python wheel as a real consumer.

Oracle Validation

The repo ships two oracle modes:

• bun run oracle Runs the strict gate. It keeps only high-confidence cross-checks that are stable enough for CI.
• bun run oracle:survey Runs the broader ecosystem survey. It includes noisier third-party validators and mutation probes to surface drift without treating every disagreement as a release blocker.

Both commands accept ORACLE_SAMPLES=<n> to trade off runtime against coverage.

bun run performance:oracles is an optional local diagnostic for the handful of specialized JavaScript oracles it covers. It is deliberately not a CI gate: those country-specific comparisons are not representative of the library as a whole. The benchmark alternates execution order and compares paired medians to reduce host noise.

Dependabot watches every JavaScript, Python, Ruby, PHP, and Rust oracle manifest. Its weekly update PRs rerun the strict correctness gates against the new upstream versions before they can merge.

Supported Identifiers

International

Countries

API

Every identifier exports the same interface:

type Validator = {
  name: string;
  localName: string;
  abbreviation: string;
  country?: CountryCode;
  entityType: "person" | "company" | "any";
  compact: (value: string) => string;
  format: (value: string) => string;
  validate: (value: string) => ValidateResult;

  // Optional metadata
  description?: string;
  sourceUrl?: string;
  lengths?: readonly number[];
  examples?: readonly string[];
  aliases?: readonly string[];
  candidatePattern?: string;

  // Available on most validators
  generate?: () => string;
};

type ValidateResult =
  | { valid: true; compact: string }
  | {
      valid: false;
      error: {
        code:
          | "INVALID_FORMAT"
          | "INVALID_LENGTH"
          | "INVALID_CHECKSUM"
          | "INVALID_COMPONENT";
        message: string;
      };
    };

Additional exports

Many person-type validators export parse(), returning structured data extracted from the identifier:

import { cz } from "@stll/stdnum";

cz.rc.parse("7103192745");
// { birthDate: Date, gender: "male" }

Validators with parse(): BA JMBG, BG ЕГН, CN RIC, CU NI, CZ RČ, DK CPR, EE IK, FI HETU, FR NIR, IT CF, KR RRN, KW Civil ID, KZ IIN, LK NIC, MX CURP, MY NRIC, NO Fødselsnr, PL PESEL, RO CNP, SE PN, SI EMŠO, SK RČ, ZA SA ID.

detectNetwork() and the CardNetwork type are top-level named exports:

import { detectNetwork } from "@stll/stdnum";
import type { CardNetwork } from "@stll/stdnum";

detectNetwork("4111111111111111");
// "visa"

Unicode handling

All validators normalize Unicode artifacts before validation: fullwidth digits, various dashes, non-breaking spaces, zero-width characters, and other common OCR/PDF copy-paste issues are handled automatically.

Development

bun install
bun run rust:check
bun run codegen:check
bun run typecheck
bun test
bun run lint     # oxlint
bun run format   # oxfmt

License

MIT