IBAN

Canonicalizes one IBAN mention per call — an electronic contiguous string or paper groups-of-four (with an optional IBAN label) — to compact electronic form.

In plain language: give it DE89370400440532013000, DE89 3704 0044 0532 0130 00, or IBAN: DE89 3704 0044 0532 0130 00 and it hands back DE89370400440532013000 when the country code is in the SWIFT IBAN Registry, the per-country fixed length holds, and the MOD 97-10 checksum passes per ISO 13616-1:2020 §4-5 (via ISO/IEC 7064:2003). A bad checksum or an unregistered country is INVALID, never a guess; shapes outside the two spellings are MISSING.

What it recognizes — and what it does not

Recognizes	Does not recognize
Electronic contiguous, 15–34 alphanumerics (`DE89370400440532013000`, lowercase folds up)	Hyphen-separated (`DE89-3704-0044-0532-0130-00`) → `MISSING`
Paper groups-of-four with single spaces (`DE89 3704 0044 0532 0130 00`, `GB29 NWBK 6016 1331 9268 19`)	Double spaces or tabs (`DE89 3704 ...`, `DE89\t3704 ...`) → `MISSING`
Fused uppercase `IBAN` label with separator (`IBAN: DE89 ...`, `IBAN - FR14 ...`, `IBAN DE89370400440532013000`)	Glued label (`IBANDE89370400440532013000`, no separator) → `MISSING`
Lowercase `iban:` prefix does not block the core (`iban:gb29nwbk60161331926819` → `GB29NWBK60161331926819`)	Irregular single-space groups (`DE89 37040 04405 32013 000`) → `MISSING`
Glued alnum tails are absorbed and rejected downstream (`DE89370400440532013000Y`, `...00n` → `INVALID`)	Prose without an IBAN shape (`not an iban`) → `MISSING`

Canonical output

Default output_format is "electronic" (identity — normalize() returns the compact string).

`output_format`	Renders	Example
(default) `electronic` / `None` / `"default"`	Compact, no spaces	`DE89370400440532013000`
`paper`	Space-separated quartets (encoding — MOD 97-10 runs on the stripped form, so the rendering re-enters exactly)	`DE89 3704 0044 0532 0130 00`

Any other value raises ContractError — including compact, which is not an offered alias (normalize outside the call if you need that spelling).

from paxman.capabilities import IBAN
import paxman

paxman.register_all_shipped()
print(paxman.canonicalize("DE89 3704 0044 0532 0130 00", IBAN.create_contract()).canonicalized_value)
print(paxman.canonicalize("IBAN: GB29 NWBK 6016 1331 9268 19", IBAN.create_contract()).canonicalized_value)
print(paxman.canonicalize("NO9386011117947", IBAN.create_contract()).canonicalized_value)
print(paxman.canonicalize("DE89370400440532013000", IBAN.create_contract(output_format="paper")).canonicalized_value)
print(paxman.canonicalize("GB29NWBK60161331926819", IBAN.create_contract(output_format="paper")).canonicalized_value)

Contract

contract = IBAN.create_contract(
    output_format=None,  # "electronic" (default), "paper"
    # plus every common field: suppress_common_words / excluded_rules / pinned_rules / year / extra_grammars
)

No grammar toggles: one grammar (iban_recognition), one rule (Section 4-iban-structure-mod97).
year filters by publication_year; e.g., year=2019 drops the ISO 13616-1:2020 rule → DE89370400440532013000 becomes INVALID.
Single-value: two distinct IBANs in one call raise MultipleMentionsError — split first per docs/recipes/segmentation.md.

Statuses

Input	Contract	Status	Value / why
`DE89370400440532013000`	defaults	`SUCCESS`	`"DE89370400440532013000"`
`DE89 3704 0044 0532 0130 00`	defaults	`SUCCESS`	`"DE89370400440532013000"` (paper recognized, spaces stripped)
`IBAN: DE89 3704 0044 0532 0130 00`	defaults	`SUCCESS`	label absorbed into the span
`not an iban`	any	`MISSING`	no IBAN shape
`DE89-3704-0044-0532-0130-00`	any	`MISSING`	hyphens are not a paper separator
`IBANDE89370400440532013000`	any	`MISSING`	glued label needs a separator
`DE89370400440532013001`	any	`INVALID`	MOD 97-10 checksum fails
`DE89 3704 0044`	any	`INVALID`	recognized short paper, per-country length fails
`DE89370400440532013000Y`	any	`INVALID`	glued tail absorbed, length/checksum fail
`DE89370400440532013000`	`year=2019`	`INVALID`	rule is 2020, dropped
`DE89370400440532013000`	`output_format="compact"`	raises `ContractError`	not an offered format
Two distinct IBANs in one call	any	raises `MultipleMentionsError`	split first

A single grammar plus a single deterministic rule yields at most one value, so AMBIGUOUS is unreachable for this capability.

Notebook snippet — normalize a mixed column

import paxman
from paxman.capabilities import IBAN
from paxman.core.domain import Resolution
from paxman.core.errors import ContractError

paxman.register_all_shipped()
contract = IBAN.create_contract()

rows = [
    "DE89370400440532013000",
    "DE89 3704 0044 0532 0130 00",
    "IBAN: GB29 NWBK 6016 1331 9268 19",
    "NO9386011117947",
    "DE89370400440532013001",
    "DE89 3704 0044",
    "DE89-3704-0044-0532-0130-00",
    "IBANDE89370400440532013000",
    "not an iban",
]

for text in rows:
    r = paxman.canonicalize(text, contract)
    val = r.canonicalized_value if r.status == Resolution.SUCCESS else "—"
    rule = r.candidates[0].validation_rule if r.candidates else "—"
    print(f"{text!r:38} → {r.status.value:10} {val!r:26} ({rule})")

try:
    IBAN.create_contract(output_format="compact")
except ContractError as e:
    print(f"compact → ContractError: {e}")

Provenance

ISO 13616-1:2020 §4-5 Structure + MOD 97-10 checksum (normative reference to ISO/IEC 7064:2003; check digits 02-98; mod97 == 1) — Section 4-iban-structure-mod97
SWIFT IBAN Registry Release 99 (Dec 2024, mirrors R100 Oct 2025) — 111 registered country codes and per-country fixed lengths (e.g. DE22, GB22, NO15) backing the allowlist/length checks

Each candidate’s validation_rule carries the section, and candidate.provenance[0].publication_year the year.