# FastX402 Tax Bracket Calculator

> FastX402 Tax Bracket Calculator is a paid API for AI agents from fastx402.tools, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-28).

Calculates US federal income tax brackets, tax owed, marginal rate, and effective rate for a given income, filing status, and tax year

## Facts

- Endpoint: GET https://fastx402.tools/tax-bracket-calculate?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastx402-tax-bracket-calculator-e6d7dae2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aunyNuReKQvodn1FVVgqy

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 fastx402-tax-bracket-calculator-e6d7dae2
```

Example prompt: What would my federal income tax look like for 2025 if I made $85,000 filing as single — break it down by bracket and tell me my marginal and effective rates.

## When to prefer this

Use this endpoint when you need a detailed federal income tax bracket breakdown for US filers across tax years 2024, 2025, or 2026, supporting all four filing statuses. It requires no API key and charges only $0.002 per call via x402 crypto micropayment, making it ideal for AI agents needing on-demand tax computation without account setup.

## Known failure modes

- Missing required query parameters (income, year, or filing_status) returns an error
- Invalid year outside 2024-2026 range returns an error
- Invalid filing_status string not matching allowed enum values returns an error
- Non-numeric income string may cause a parsing error
- Payment failure via x402 protocol returns 402 Payment Required

## How this service works

216 pay-per-call tools for AI agents, from $0.001 per request in USDC on Base or Solana with x402. No account, no API key.

## Output

Returns a JSON object with the tax year, income, filing status, an array of bracket objects (each with rate, income in bracket, and tax paid in that bracket), total tax owed in dollars, marginal tax rate as a percentage, and effective tax rate as a decimal percentage.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "income",
      "year",
      "filing_status"
     ],
     "properties": {
      "year": {
       "type": "string",
       "description": "Tax year: 2024, 2025, or 2026"
      },
      "income": {
       "type": "string",
       "description": "Taxable income in USD, e.g. 85000"
      },
      "filing_status": {
       "type": "string",
       "description": "Filing status: single, married_joint, married_separate, or head_of_household"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "year": {
       "type": "integer"
      },
      "income": {
       "type": "integer"
      },
      "brackets": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "tax": {
          "type": "number"
         },
         "rate": {
          "type": "integer"
         },
         "income_in_bracket": {
          "type": "integer"
         }
        }
       }
      },
      "tax_owed": {
       "type": "integer"
      },
      "filing_status": {
       "type": "string"
      },
      "marginal_rate": {
       "type": "integer"
      },
      "effective_rate": {
       "type": "number"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "year": 2025,
  "income": 85000,
  "brackets": [
   {
    "tax": 1192.5,
    "rate": 10,
    "income_in_bracket": 11925
   },
   {
    "tax": 4386,
    "rate": 12,
    "income_in_bracket": 36550
   },
   {
    "tax": 8035.5,
    "rate": 22,
    "income_in_bracket": 36525
   }
  ],
  "tax_owed": 13614,
  "filing_status": "single",
  "marginal_rate": 22,
  "effective_rate": 16.02
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastx402-tax-bracket-calculator-e6d7dae2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fastx402.tools](https://www.zero.xyz/host/fastx402.tools/llms.txt)