Send a photo of a Bissau-Guinean passport and get structured data back in the same HTTP response — the machine-readable zone parsed, the ICAO 9303 check digits verified and the visual fields extracted. No SDK to install, no queue to poll.
A Guinea-Bissau passport follows the ICAO 9303 standard: a two-line, 44-character
machine-readable zone (format TD3) printed at the foot of the data page,
above the human-readable visual inspection zone. Its first five characters are P<GNB — the document code, then the issuing state as the ISO
3166-1 alpha-3 code GNB. The API reads both zones,
cross-checks the MRZ check digits, and returns one response shape with every key present.
Guinea-Bissau is GW in an alpha-2 list and GNB in the zone, and no amount of appending gets from one to the other — GW is not even a prefix of GNB. A store holding the two-letter code needs the ISO 3166-1 table to reach the three-letter one the machine-readable zone actually prints.
9303 defines three zone layouts, and the API reads all three. Below is one invented holder — she is nobody, and paradeigma is the Greek word for example — in each layout, with GNB as the issuing state. Every check digit is computed from the characters beside it rather than typed in, so each zone here validates.
2 lines of 44. Nationality GNB. Issuing state and nationality are both GNB: a passport certifies the nationality of the state that issued it.
P<GNBPARADEIGMA<<ELENI<SOFIA<<<<<<<<<<<<<<<<
AM73045184GNB9403084F3203101PN48291630<<<<722 lines of 36. Nationality GRC. Issued by GNB to a GRC national, so the two codes differ. The name has 31 characters here instead of the passport's 39.
I<GNBPARADEIGMA<<ELENI<SOFIA<<<<<<<<
TR61850420GRC9403084F2911043<<<<<<<23 lines of 30. Nationality GRC. Three lines of 30, with the name on a line of its own. The document code is ID — 9303 part 5 fixes the first character as A, C or I and leaves the second to the issuing state.
IDGNBAK472913<4PN48291630<<<<<
9403084F3405204GRC<<<<<<<<<<<9
PARADEIGMA<<ELENI<SOFIA<<<<<<<No check digit covers the issuing state: on all three layouts the arithmetic runs over the document number, the dates and the optional data, never over the three characters that say who issued the document. A zone whose digits all pass has not proved it came from Guinea-Bissau — the visual zone and the document's own security features do that.
Paste an MRZ into the MRZ checker to validate its check digits, or build one with the MRZ generator.
Every recognised Bissau-Guinean passport returns the same structured fields. A value
that could not be read is null, never a missing key.
See every field in the document field explorer.
Run this against the public sandbox — no registration, real recognition, free for a limited number of documents and 10 requests per hour per IP. Swap the sandbox key for your own live key to keep recognising Bissau-Guinean passports.
curl -X POST https://api.doc.cheap/v1/scans \
-H "Authorization: Bearer sk_sandbox_public" \
-H "Content-Type: application/json" \
-d "{\"image\": \"$(base64 < document.jpg | tr -d '\n')\"}"This page covers what is specific to Guinea-Bissau. The four pages below carry everything that is not.
The call above with a real document, in curl, JavaScript and Python, and every key of the answer read out.
Why a document prints the same facts twice, which zone to believe when they disagree, and what the check digits above can and cannot prove.
The zone is Latin transliteration; the visual zone is not. Which reading carries the original script, and how a language identifier resolves to a language.
Every error code the API can answer with, in one table: what causes it, whether a retry can succeed, and whether the call was billed.
First successful call in under 60 seconds, 1¢ per document, and the document image is never stored.
You pay only for documents we actually recognise.
Blurry photo, no document in frame, unknown type — free. You never pay for a failed scan.