About Validatelist
Validatelist is a free, client-side reference for checking the format andchecksum of common ID and identifier types — VAT numbers, IBANs, tax IDs, and national identifiers. Every validator runs in your browser. Nothing you enter is sent anywhere. See the privacy policy for details.
What "valid" means on this site
Every identifier format defined by a government, bank, or standards body follows a documented structure: a fixed length, allowed characters, a country or issuer prefix, and often a checksum digit that lets you catch typos without looking anything up. Validatelist checks exactly that — and only that:
- Format — does the value match the documented pattern for that ID type (length, character set, structure), using a regular expression derived from the published specification?
- Checksum — where the ID type defines a check digit or check character, does it satisfy the documented algorithm? Validatelist implements the algorithms it needs from scratch, including mod-97 (used for IBAN and UK VAT numbers), Luhn-mod-36 (used for GSTIN), and the Verhoeff algorithm (used for Aadhaar numbers). Where an ID type has no public checksum algorithm — PAN is an example — Validatelist checks format only, and says so on that validator's page.
A green "valid" result means: this value is well-formed and internally consistent for this ID type. It is a strong, fast, and completely free signal for catching typos, OCR errors, and copy-paste mistakes before they cause problems downstream.
What Validatelist does not do
A validator here cannot and does not confirm that an identifier is currently registered, active, or belongs to a real, existing person or business. Format-and-checksum validity is a necessary condition for a real-world ID, not a sufficient one — a well-formed, checksum-valid number can still be unissued, revoked, or fabricated. Confirming live registration requires querying the relevant official registry (for example, the EU's VIES system for VAT numbers, or a national tax authority's lookup service), which is a different kind of check than this site performs. Where an official registry exists for an ID type, the validator page links to it directly rather than trying to replicate it.
How the validators are built
Each validator is defined by a small, explicit record: the country/issuer, the regular expression for its format, a worked example, common mistakes ("gotchas") people run into, and — where applicable — which checksum algorithm applies. That record drives the input field, the pass/fail result, the human-readable rules table, and the visible regex on every validator page, so the page and the underlying logic can never drift apart.
The checksum algorithms themselves are implemented as small, isolated functions and covered by automated tests that check them against known-valid and known-invalid example values, including official worked examples where the issuing body publishes one. The logic is plain, dependency-free JavaScript/TypeScript — there is no black box and no third-party validation API in the loop.
Editorial standard
We hold every validator to the same bar:
- Accuracy first. Format rules and checksum algorithms are sourced from official specifications and cross-checked against real, published example values before a validator page goes live.
- Honest scope. Every page is explicit that it checks format and checksum, not live registration status, and links to the relevant official registry where one exists.
- No fabricated authority. We do not claim credentials, certifications, or affiliations we don't have. Validatelist is an independent reference tool, not a government or financial institution.
- Corrections welcome. ID formats occasionally change when an issuing body revises its standard. If you find a validator that's out of date or behaving incorrectly, please tell us — see the corrections policy on that page.
Who's behind this
Validatelist is built and maintained by the Validatelist team. It's a small, independent project with no team page or bios to publish yet — we'd rather this page stay honest than pad it with invented credentials. If that changes, this section will be updated.