Tax Calculation API

Calculate federal and state tax liability, estimate refunds, and analyze tax scenarios.

POST/v1/tax/calculate

Calculate tax liability and estimated refund based on income and withholding data.

Request Parameters

income (required)

Total income amount in dollars

federal_withheld (required)

Federal tax withheld in dollars

state_withheld (optional)

State tax withheld in dollars

filing_status (optional)

single, married_joint, married_separate, head_of_household. Default: single

deductions (optional)

Array of deduction objects with amount and category

credits (optional)

Array of tax credit objects with amount and type

Example Request

curl https://api.taxu.io/v1/tax/calculate \
  -H "Authorization: Bearer your_api_key" \
  -H "Content-Type: application/json" \
  -d '{
    "income": 75000,
    "federal_withheld": 12500,
    "state_withheld": 3750,
    "filing_status": "single",
    "deductions": [
      {
        "category": "student_loan_interest",
        "amount": 2500
      }
    ],
    "credits": [
      {
        "type": "savers_credit",
        "amount": 1000
      }
    ]
  }'

Response

{
  "id": "calc_1234567890",
  "object": "tax_calculation",
  "created": 1704067200,
  "total_income": 75000.00,
  "adjusted_gross_income": 72500.00,
  "taxable_income": 57900.00,
  "standard_deduction": 14600.00,
  "itemized_deductions": 2500.00,
  "federal_tax_liability": 8234.50,
  "state_tax_liability": 3625.00,
  "total_tax_liability": 11859.50,
  "total_withheld": 16250.00,
  "estimated_refund": 4390.50,
  "amount_owed": 0.00,
  "effective_tax_rate": 15.81,
  "marginal_tax_rate": 22.00,
  "confidence_level": "high",
  "confidence_percentage": 96,
  "tax_year": 2024,
  "breakdown": {
    "federal": {
      "bracket_10": 1160.00,
      "bracket_12": 4266.00,
      "bracket_22": 2808.50,
      "total": 8234.50
    },
    "state": {
      "rate": 5.00,
      "total": 3625.00
    }
  }
}

GET/v1/tax/calculations

List all tax calculations for the authenticated user.

Query Parameters

tax_year (optional)

Filter by tax year (e.g., 2024)

limit (optional)

Number of results to return (default: 10, max: 100)

Example Request

curl https://api.taxu.io/v1/tax/calculations?tax_year=2024&limit=10 \
  -H "Authorization: Bearer your_api_key"

Response

{
  "object": "list",
  "data": [
    {
      "id": "calc_1234567890",
      "object": "tax_calculation",
      "created": 1704067200,
      "total_income": 75000.00,
      "estimated_refund": 4390.50,
      "tax_year": 2024
    }
  ],
  "has_more": false,
  "total_count": 1
}

Tax Calculation Details

2024 Tax Brackets (Single Filers)

$0 - $11,60010%

$11,601 - $47,15012%

$47,151 - $100,52522%

$100,526 - $191,95024%

$191,951 - $243,72532%

$243,726 - $609,35035%

$609,351+37%

Standard Deductions (2024)

Single$14,600

Married Filing Jointly$29,200

Head of Household$21,900