W-2 Data Extraction API: Integrate Tax Form Data Into Your Applications

Why Integrate a W-2 Extraction API?

Every tax season, HR and payroll teams face the same bottleneck: employees submit W-2 forms for verification, income confirmation, or benefits applications — and someone has to key that data manually. A W-2 extraction API eliminates that bottleneck entirely.

With an API integration, your application can accept a W-2 upload and immediately receive structured JSON back — all 20+ boxes extracted, labeled, and ready to use.

What the API Returns

A complete W-2 extraction returns:

{
  "tax_year": "2025",
  "employer_ein": "12-3456789",
  "employer_name": "Acme Corporation",
  "employer_address": "123 Main St, Springfield, IL 62701",
  "employee_name": "Jane Smith",
  "employee_ssn_last4": "6789",
  "box1_wages": 85000.00,
  "box2_federal_tax": 12750.00,
  "box3_ss_wages": 85000.00,
  "box4_ss_tax": 5270.00,
  "box5_medicare_wages": 85000.00,
  "box6_medicare_tax": 1232.50,
  "box12_codes": [{"code": "D", "amount": 6500.00}],
  "box13_retirement": true,
  "state_wages": 85000.00,
  "state_tax": 4250.00,
  "state": "IL"
}

Common Integration Use Cases

Mortgage and Lending Applications

Lenders need to verify borrower income. Instead of manually reviewing W-2s, an API integration lets the borrower upload their W-2 during the application — income is verified automatically, processing time drops from days to minutes.

Payroll System Import

When employees join a company mid-year or need to reconcile payroll data, HR teams can use W-2 extraction to import prior employer data directly rather than re-entering it manually.

Tax Preparation Software

Tax prep apps can let users snap a photo or upload their W-2 and pre-fill the entire return automatically. The API handles extraction; the app handles the UX.

Benefits Verification

Programs that verify income eligibility (housing assistance, benefits enrollment, student aid) can automate income confirmation by extracting Box 1 wages directly from the W-2.

API Integration in 3 Steps

Upload: POST the W-2 PDF or image (base64 or multipart form)
Extract: Receive JSON with all boxes extracted and labeled
Use: Map fields to your data model and store/display as needed

Handling Multiple W-2 Forms

Many workers have multiple W-2s (multiple employers, multiple states). The API handles multi-page PDF uploads and can process several W-2s in a single request, returning an array of results — one per W-2 form detected.

Start Extracting W-2 Data

Visit w2extractor.com to test the API with your own W-2 documents. JSON output, all boxes, ready for your integration.