Rule of 40 (SaaS health) API

Rule of 40 score = revenue growth % + profit margin %, passing if >= 40 — the canonical SaaS balance-of-growth-and-profitability heuristic, with a per-factor breakdown and rating bucket. Answers 'do I pass the Rule of 40', 'what's my growth-plus-margin score', 'is my SaaS healthy'.

Price$0.01per request

MethodPOST

Route/v1/calc/biz-rule-of-40

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

calcrule-of-40saasgrowthprofitabilityhealth-scoreopsfinance

API URLhttps://x402.hexl.dev/v1/calc/biz-rule-of-40

Integration docs

Example request

{
  "growthRatePercent": 30,
  "profitMarginPercent": 15
}

Example response

{
  "formula": "score = growthRatePercent + profitMarginPercent ; pass if >= 40",
  "score": 45,
  "passes": true,
  "rating": "healthy",
  "breakdown": [
    {
      "factor": "growthRatePercent",
      "value": 30
    },
    {
      "factor": "profitMarginPercent",
      "value": 15
    }
  ]
}

Input schema

{
  "type": "object",
  "required": [
    "growthRatePercent",
    "profitMarginPercent"
  ],
  "properties": {
    "growthRatePercent": {
      "type": "number",
      "examples": [
        30
      ]
    },
    "profitMarginPercent": {
      "type": "number",
      "examples": [
        15
      ]
    }
  }
}

Output schema

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