curl --request POST \
  --url https://api.iotools.cloud/v1/tool/side-hustle-income-tax-calculator \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "filingStatus": "single",
  "grossIncome": "50000",
  "expenses": "5000",
  "otherIncome": "0"
}
'

{
  "tool": "side-hustle-income-tax-calculator",
  "tool_version": "1.0.1",
  "outputs": {
    "taxBreakdown": [
      {
        "description": "Net Self-Employment Income",
        "amount": "$45,000.00"
      },
      {
        "description": "Self-Employment Tax",
        "amount": "$6,358.30"
      },
      {
        "description": "Social Security (12.4%)",
        "amount": "$5,153.13"
      },
      {
        "description": "Medicare (2.9%)",
        "amount": "$1,205.17"
      },
      {
        "description": "Additional Medicare (0.9%)",
        "amount": "$0.00"
      },
      {
        "description": "SE Tax Deduction (50%)",
        "amount": "-$3,179.15"
      },
      {
        "description": "Estimated Federal Income Tax",
        "amount": "$2,980.00"
      },
      {
        "description": "Total Estimated Tax",
        "amount": "$9,338.30"
      },
      {
        "description": "Effective Tax Rate",
        "amount": "20.8%"
      },
      {
        "description": "Quarterly Payment",
        "amount": "$2,334.57"
      }
    ],
    "quarterlyAdvice": "You should make quarterly estimated tax payments. Your estimated annual tax of $9,338.30 exceeds $1,000. The IRS requires estimated payments to avoid underpayment penalties. Pay $2,334.57 per quarter (due April 15, June 15, September 15, and January 15 of the following year)."
  },
  "credits_used": 3,
  "credits_remaining": null
}