us_i9_form

USCIS Form I-9 (Employment Eligibility Verification)

Completed USCIS Form I-9: Section 1 (employee information and attestation) and Section 2 (List A or List B + C documents examined by the employer).

Category: Employment
Country: United States
Extracted fields: 23 fields
Cost: 1 credit

us_i9_formspecimen

Last name
First name
Middle initial
Other last names
Address
Date of birth
Social Security number (SSN)
Email
Phone

What it checks

National identifiers. Official checksum or format of the number (NIF, CPF, CURP, RUT, SSN…).us_ssn, us_uscis
Holder. Name, number or date of birth match what you expect.
Age. Minimum or maximum age from the date of birth.

Extracted fields

Last namelast_name
First namefirst_name
Middle initialmiddle_initial
Other last namesother_last_names
Addressaddress
Date of birthbirth_date
Social Security number (SSN)ssn
Emailemail
Phonephone
Citizenship statuscitizenship_status
USCIS number (A-number)uscis_number
I94 numberi94_number
Foreign passport numberforeign_passport_number
Work authorization expirywork_authorization_expiry
Employee signature dateemployee_signature_date
Documentsdocuments
First day of employmentfirst_day_of_employment
Employer nameemployer_name
Employer titleemployer_title
Business namebusiness_name
Business addressbusiness_address
Employer signature dateemployer_signature_date
Form editionform_edition

Sample request

curl https://api.constaia.com/v1/analyze \
  -H "Authorization: Bearer $CONSTAIA_API_KEY" \
  -F "file=@document.pdf" \
  -F 'options={
    "expect": "us_i9_form",
    "checks": {
      "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": "us_i9_form",
    "label": "USCIS Form I-9 (Employment Eligibility Verification)",
    "confidence": 0.97
  },
  "verdict": {
    "expected": [
      "us_i9_form"
    ],
    "match": true,
    "status": "valid",
    "reasons": [
      {
        "code": "type_match",
        "severity": "info",
        "message": "The document is: USCIS Form I-9 (Employment Eligibility Verification)."
      }
    ]
  },
  "fields": {
    "last_name": {
      "value": "SPECIMEN",
      "confidence": 0.99,
      "validated": true
    },
    "first_name": {
      "value": "JANE",
      "confidence": 0.98,
      "validated": null
    },
    "middle_initial": {
      "value": "Q",
      "confidence": 0.97,
      "validated": null
    },
    "address": {
      "value": "2570 24TH STREET, SACRAMENTO, CA 95818",
      "confidence": 0.96,
      "validated": null
    },
    "birth_date": {
      "value": "1985-07-30",
      "confidence": 0.99,
      "validated": null
    },
    "ssn": {
      "value": "512-34-5678",
      "confidence": 0.98,
      "validated": null
    },
    "citizenship_status": {
      "value": "1",
      "confidence": 0.97,
      "validated": null
    },
    "employee_signature_date": {
      "value": "2026-09-01",
      "confidence": 0.96,
      "validated": null
    },
    "documents": {
      "value": [
        {
          "list": "B",
          "title": "Driver's license",
          "issuing_authority": "CA DMV",
          "document_number": "I1234568",
          "expiry_date": "2031-07-30"
        },
        {
          "list": "C",
          "title": "Social Security card",
          "issuing_authority": "SSA",
          "document_number": "512-34-5678"
        }
      ],
      "confidence": 0.99,
      "validated": null
    },
    "first_day_of_employment": {
      "value": "2026-09-01",
      "confidence": 0.98,
      "validated": null
    },
    "business_name": {
      "value": "SPECIMEN CORP",
      "confidence": 0.97,
      "validated": null
    },
    "employer_signature_date": {
      "value": "2026-09-03",
      "confidence": 0.96,
      "validated": null
    },
    "form_edition": {
      "value": "01/20/25",
      "confidence": 0.99,
      "validated": null
    }
  },
  "checks": [
    {
      "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…

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