pt_citizen_card

Portuguese Citizen Card (Cartão de Cidadão)

Portuguese identity card (Cartão de Cidadão), chip card with TD1 MRZ; the back shows the tax number (NIF), social security number (NISS) and health service user number.

Category: Identity
Country: Portugal
Extracted fields: 16 fields
Cost: 1 credit

pt_citizen_cardspecimen

Document number
First name
Last name
Sex
Nationality
Date of birth
Issue date
Expiry date
Issuing country

What it checks

MRZ ICAO 9303. Check digits of the machine readable zone.
MRZ vs printed data. The MRZ matches the visible data.
National identifiers. Official checksum or format of the number (NIF, CPF, CURP, RUT, SSN…).pt_cc, pt_nif
Holder. Name, number or date of birth match what you expect.
Age. Minimum or maximum age from the date of birth.
Validity. Not expired on the reference date.

Extracted fields

Document numberdocument_number
First namefirst_name
Last namelast_name
Sexsex
Nationalitynationality
Date of birthbirth_date
Issue dateissue_date
Expiry dateexpiry_date
Issuing countryissuing_country
Mrzmrz
Civil id numbercivil_id_number
Tax idtax_id
Social security numbersocial_security_number
Health numberhealth_number
Heightheight
Parents' namesparents

Sample request

curl https://api.constaia.com/v1/analyze \
  -H "Authorization: Bearer $CONSTAIA_API_KEY" \
  -F "file=@document.pdf" \
  -F 'options={
    "expect": "pt_citizen_card",
    "checks": {
      "not_expired": true,
      "holder": {
        "full_name": "Carmen Especimen Ruiz"
      }
    },
    "storage": "none"
  }'

Sample response

Fictitious data. Shortened response.

200 OK · application/json

{
  "id": "an_01J9Z3K8QW4T6Y2B7N5M1R0PXC",
  "object": "analysis",
  "status": "completed",
  "livemode": false,
  "document": {
    "type": "pt_citizen_card",
    "label": "Portuguese Citizen Card (Cartão de Cidadão)",
    "confidence": 0.97
  },
  "verdict": {
    "expected": [
      "pt_citizen_card"
    ],
    "match": true,
    "status": "valid",
    "reasons": [
      {
        "code": "type_match",
        "severity": "info",
        "message": "The document is: Portuguese Citizen Card (Cartão de Cidadão)."
      }
    ]
  },
  "fields": {
    "document_number": {
      "value": "12345678 9 ZZ1",
      "confidence": 0.99,
      "validated": true
    },
    "first_name": {
      "value": "MARIA",
      "confidence": 0.98,
      "validated": null
    },
    "last_name": {
      "value": "ESPÉCIME",
      "confidence": 0.97,
      "validated": null
    },
    "sex": {
      "value": "F",
      "confidence": 0.96,
      "validated": null
    },
    "nationality": {
      "value": "PRT",
      "confidence": 0.99,
      "validated": null
    },
    "birth_date": {
      "value": "1985-07-30",
      "confidence": 0.98,
      "validated": null
    },
    "issue_date": {
      "value": "2023-03-15",
      "confidence": 0.97,
      "validated": null
    },
    "expiry_date": {
      "value": "2033-03-14",
      "confidence": 0.96,
      "validated": null
    },
    "issuing_country": {
      "value": "PRT",
      "confidence": 0.99,
      "validated": null
    },
    "mrz": {
      "value": "I<PRT1234567897ZZ1<<<<<<<<<<<<\n8507309F3303148PRT<<<<<<<<<<<7\nESPECIME<<MARIA<<<<<<<<<<<<<<<",
      "confidence": 0.98,
      "validated": null
    },
    "civil_id_number": {
      "value": "12345678 9",
      "confidence": 0.97,
      "validated": null
    },
    "tax_id": {
      "value": "123456789",
      "confidence": 0.96,
      "validated": null
    },
    "social_security_number": {
      "value": "11234567890",
      "confidence": 0.99,
      "validated": null
    },
    "health_number": {
      "value": "123456789",
      "confidence": 0.98,
      "validated": null
    },
    "height": {
      "value": "1,68",
      "confidence": 0.97,
      "validated": null
    }
  },
  "checks": [
    {
      "code": "mrz_checksums",
      "passed": true,
      "message": "The MRZ check digits are correct."
    },
    {
      "code": "mrz_matches_visual",
      "passed": true,
      "message": "The MRZ matches the printed data."
    },
    {
      "code": "id_number",
      "passed": true,
      "message": "id_number"
    }
  ],
  "warnings": [],
  "storage": {
    "mode": "none",
    "file_deleted_at": "2026-09-29T10:00:02Z",
    "expires_at": null
  },
  "usage": {
    "credits": 1,
    "pages": 1
  }
}

FAQ

Does Constaia prove the document is authentic?

No. It checks the type, data consistency and your rules, and flags signals such as a possible edit or a screen photo. That does not prove authenticity.

Is a copy of the document kept?

No, unless you ask for it. With storage "none" (the default) the file is deleted when the analysis ends.

And for the record…

Create your account, copy the test key and validate your first document in five minutes.

Create a free account Talk to sales