# US Federal Income Tax Estimator

> US Federal Income Tax Estimator is a paid API for AI agents from api.agentstools.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Estimates US federal (and optionally state) income tax for a given year, returning taxable income, total tax, marginal and effective rates, and a per-bracket breakdown.

## Facts

- Endpoint: GET https://api.agentstools.dev/tax/income
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/us-federal-income-tax-estimator-f4e03c16
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Krd2hi1D-_h5KNF4iqMw_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability us-federal-income-tax-estimator-f4e03c16
```

Example prompt: What's my estimated federal income tax for 2025 if I made $120,000 as a single filer — and can you also include a California state estimate?

## When to prefer this

Use this endpoint when you need a fast, pure-computation estimate of US federal income tax liability with bracket-level detail and an optional state estimate, without needing to file or submit anything. Prefer this over generic tax software APIs when you want a lightweight, per-call calculation suitable for embedding in financial planning workflows or chatbot responses.

## Known failure modes

- Missing required gross_income parameter returns a 400 error
- Invalid filing_status enum value returns a 400 validation error
- Invalid or unrecognized state code may return an error or omit state estimate
- Negative gross_income value rejected with 400 error
- Unsupported tax_year may return a 400 or fall back to default

## How this service works

US federal income tax estimate for a tax year: taxable income, tax, marginal and effective rate, per-bracket breakdown, with an optional state estimate. Pure computation over your inputs, not tax advice.

## Output

Returns taxable income after deductions, total federal tax owed, marginal and effective tax rates, a line-by-line breakdown of tax owed per bracket, and optionally a state-level tax estimate for the specified state.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "gross_income"
     ],
     "properties": {
      "state": {
       "type": "string",
       "description": "Optional two-letter state code for a state estimate"
      },
      "tax_year": {
       "type": "integer",
       "description": "Tax year, default 2026"
      },
      "deductions": {
       "type": "number",
       "description": "Total deductions; omit to use the standard deduction"
      },
      "gross_income": {
       "type": "number",
       "description": "Total gross income before deductions (>= 0)"
      },
      "filing_status": {
       "enum": [
        "single",
        "married_jointly",
        "married_separately",
        "head_of_household"
       ],
       "type": "string",
       "description": "Filing status, default single"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/us-federal-income-tax-estimator-f4e03c16/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.agentstools.dev](https://www.zero.xyz/host/api.agentstools.dev/llms.txt)