Docs · Validators

`iban` validator

Format + mod-97 checksum, with optional country allow-list.

One of 19 validator types · pure compute, no AI cost

Reference

Format

Strips whitespace and uppercases, then matches `/^[A-Z]{2}\d{2}[A-Z0-9]{11,30}$/`. If `countries` is set, the 2-letter prefix must be in that list. Final step is the standard IBAN mod-97 = 1 check, computed in 7-char chunks (no BigInt, edge-worker safe).

Examples

CH93 0076 2011 6238 5295 7 (CH, 21 chars)
DE89 3704 0044 0532 0130 00 (DE, 22 chars)
GB82 WEST 1234 5698 7654 32 (GB, 22 chars, alpha bank code)

How it runs

Implementation

A faithful summary of lib/validators.ts. Validators are pure functions and run identically in the Worker, the Workbench and the MCP server — one implementation, so the three cannot disagree about whether a value is valid.

lib/validators.ts

function validIban(value, params) {
  const v = value.replace(/\s+/g, '').toUpperCase()
  if (!/^[A-Z]{2}\d{2}[A-Z0-9]{11,30}$/.test(v)) return fail('iban_format', 'bad IBAN format')
  const countries = Array.isArray(params.countries) ? params.countries : null
  if (countries && !countries.includes(v.slice(0, 2))) {
    return fail('iban_country', `country ${v.slice(0, 2)} not allowed`)
  }
  const rearranged = v.slice(4) + v.slice(0, 4)
  const expanded = rearranged.replace(/[A-Z]/g, (c) => String(c.charCodeAt(0) - 55))
  let mod = 0
  for (let i = 0; i < expanded.length; i += 7) {
    mod = Number(`${mod}${expanded.slice(i, i + 7)}`) % 97
  }
  return mod === 1 ? OK : fail('iban_checksum', 'IBAN checksum failed')
}

Config

Use in a template

Validators attach to a field on a custom template. The cascade runs them after mapping but before commit; failures surface in the per-row validation report.

template.yaml

fields:
  - column: iban
    type: string
    validators:
      - type: iban
        countries: [CH, LI, DE, FR, IT]

Watch out

Common gotchas

Country length is enforced only via the global 4–32 char total (`[A-Z0-9]{11,30}` after the 4-char prefix). Swiss IBANs are 21 chars, German 22, Maltese 31 — the validator does not enforce per-country length.
Whitespace is stripped before checksum; case is normalised. `"ch93 0076..."` works.
No bank-code lookup. A syntactically valid IBAN can still point at a closed account.
Opt-in `strict: true` enforces per-country length against the SWIFT IBAN Registry (CH=21, DE=22, FR=27, GB=22, MT=31, …) in addition to the mod-97 checksum. A wrong length returns `iban_length`; an unrecognised country prefix returns `iban_country`. Default behavior is unchanged.

Where it runs

Three routes, no AI cost.

POST/v1/validate-rowValidate one row against a template. Stateless, no key, pure compute — the fastest way to try iban against a real value.no key
POST/v1/uploads/:id/validateRun every field validator over the parsed upload, without committing. Returns errors and warnings per row.read
POST/v1/uploads/:id/commitValidates on the way out. skip_invalid_rows drops the failures instead of failing the commit.commit

Validators are pure functions, so they add nothing to the AI bill. Every map draws a small flat per-map fee from your prepaid token wallet ($10 minimum, shared across the phi-cloud suite); only columns that reach the metered LLM layer, plus any-to-any convert and structural reshape, bill real AI tokens. See pricing

Catalogue

Related templates

Employee rosteremployee_roster_v1
Names, AHV/GLN, contract type, address.
Fields · iban
Supplier inventorysupplier_inventory_v1
Supplier catalogue with GTIN/IBAN/GLN.
Fields · iban
Bank accountsbank_accounts_v1
Bank account details with IBAN/BIC validation.
Fields · iban
Employeesemployees_v1
Employee master records with identity, contact, and bank details. Contains PII.
Fields · iban
Payrollpayroll_v1
Payroll runs: gross salary, pay period, payout bank details. Contains sensitive PII.
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Explore

All 19 validator types

The complete list a template field can declare. There is no SNOMED validator — it required an affiliate licence, no template used it, and it was removed in 2026.

Back to the documentation index or browse the template catalogue.

Ready when you are

Validate every row — before it lands.

Attach checksum-strict validators to any field, and gate risky commits behind the requires_hitl flag. One key runs the whole cascade.

Get an API key See pricing

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iban validator