FIRE number (financial independence) API

Compute the financial-independence target using fireNumber = annualExpenses/(SWR/100) (≈25× expenses at a 4% safe withdrawal rate), returning the target, expense multiple, remaining gap, and progress percent versus current savings. Answers 'what is my FIRE number','how much do I need to retire on 40k a year','am I on track for financial independence'.

Price$0.01per request

MethodPOST

Route/v1/calc/pf-fire-number

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

calcfirefinancial-independenceretirement4-percent-rulesavingspersonal-financetarget

API URLhttps://x402.hexl.dev/v1/calc/pf-fire-number

Integration docs

Example request

{
  "annualExpenses": 40000,
  "safeWithdrawalRatePercent": 4,
  "currentSavings": 200000
}

Example response

{
  "formula": "fireNumber = annualExpenses / (SWR/100)  (≈ 25× expenses at 4%)",
  "fireNumber": 1000000,
  "multipleOfExpenses": 25,
  "currentSavings": 200000,
  "remainingToFire": 800000,
  "progressPercent": 20,
  "breakdown": {
    "annualExpenses": 40000,
    "safeWithdrawalRatePercent": 4
  }
}

Input schema

{
  "type": "object",
  "required": [
    "annualExpenses"
  ],
  "properties": {
    "annualExpenses": {
      "type": "number",
      "examples": [
        40000
      ]
    },
    "safeWithdrawalRatePercent": {
      "type": "number",
      "description": "default 4",
      "examples": [
        4
      ]
    },
    "currentSavings": {
      "type": "number",
      "examples": [
        200000
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}