Safe withdrawal rate (4% rule) API

Compute sustainable retirement spending from a portfolio using the Trinity-study safe-withdrawal-rate rule annualWithdrawal = portfolio·(rate/100) (default 4%), returning annual and monthly draw plus a risk rating from very-conservative to high-depletion. Answers 'how much can I withdraw from 1M','4% rule annual income','safe monthly withdrawal'.

Price$0.01per request

MethodPOST

Route/v1/calc/pf-withdrawal-rate

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

calcwithdrawal-rate4-percent-ruletrinity-studyretirementfirepersonal-financedrawdown

API URLhttps://x402.hexl.dev/v1/calc/pf-withdrawal-rate

Integration docs

Example request

{
  "portfolio": 1000000,
  "withdrawalRatePercent": 4
}

Example response

{
  "formula": "annualWithdrawal = portfolio · (rate/100)  (Trinity study 4% rule)",
  "annualWithdrawal": 40000,
  "monthlyWithdrawal": 3333.33,
  "withdrawalRatePercent": 4,
  "rating": "safe (Trinity 4% rule)",
  "breakdown": {
    "portfolio": 1000000,
    "withdrawalRatePercent": 4
  }
}

Input schema

{
  "type": "object",
  "required": [
    "portfolio"
  ],
  "properties": {
    "portfolio": {
      "type": "number",
      "examples": [
        1000000
      ]
    },
    "withdrawalRatePercent": {
      "type": "number",
      "description": "default 4",
      "examples": [
        4
      ]
    }
  }
}

Output schema

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