# Refi Break-Even Calculator

> Refi Break-Even Calculator is a paid API for AI agents from x402.agentutility.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Calculates how many months it takes to recoup mortgage refinance closing costs and computes net savings over a specified hold horizon.

## Facts

- Endpoint: POST https://x402.agentutility.ai/refi-break-even-calculator
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/refi-break-even-calculator-6d22055e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yo0rkxoCAUg5najr7u3Im

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 refi-break-even-calculator-6d22055e -d '<json body>'
```

Example prompt: I have a $350,000 mortgage at 7.1% and I can refinance to 6.2%. Closing costs would be about $6,500. I plan to stay in the house for 5 years — how many months until I break even, and what are my total net savings?

## When to prefer this

Use this endpoint when you need a fast, focused break-even and savings computation for a single mortgage refinance scenario. Prefer it over a full refinance-analysis-calculator when the user only needs to know payback months, payment delta, and net savings — not a comprehensive amortization table or side-by-side loan comparison. Best suited for quick yes/no refi decisions driven by closing cost payback period.

## Known failure modes

- Missing required inputs (loan balance, rates, closing costs) returns a validation error
- New rate higher than or equal to current rate may return zero or negative savings with a warning
- Extremely short hold horizons where break-even is never reached return an indication that refinancing is not beneficial
- Invalid numeric values or negative inputs return a 400-level error
- Payment failure or insufficient USDC balance returns a 402 error

## How this service works

Calculates how many months a mortgage refinance takes to pay back its closing costs. Same backend as refinance-analysis-calculator, focused on break-even months, net savings over hold horizon, and payment delta. Use it as a refi break-even calculator, closing-cost payback calculator, or mortgage refinance savings API.

## Output

Returns the number of months until refinance closing costs are fully recouped, the monthly payment delta between old and new rates, and the total net savings (or loss) over the specified hold horizon in dollars.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "required": [
      "current_loan_balance",
      "current_rate",
      "new_rate",
      "remaining_years"
     ],
     "properties": {
      "new_rate": {
       "type": "number",
       "description": "Proposed annual interest rate as percent, e.g. 5.95."
      },
      "current_rate": {
       "type": "number",
       "description": "Current annual interest rate as percent, e.g. 7.25."
      },
      "closing_costs": {
       "type": "number",
       "description": "Total refinance closing costs financed or paid out of pocket. Default 0."
      },
      "months_to_stay": {
       "type": "number",
       "description": "Expected holding period in months. Default is new term length."
      },
      "new_term_years": {
       "type": "number",
       "description": "Proposed refinance term in years. Defaults to remaining_years."
      },
      "remaining_years": {
       "type": "number",
       "description": "Years remaining on current loan."
      },
      "current_loan_balance": {
       "type": "number",
       "description": "Current unpaid principal balance."
      },
      "current_monthly_payment": {
       "type": "number",
       "description": "Optional actual current monthly payment override."
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "grade": {
       "type": "string"
      },
      "score": {
       "type": "number"
      },
      "source": {
       "type": "string"
      },
      "drivers": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "name": {
          "type": "string"
         },
         "note": {
          "type": "string"
         },
         "score": {
          "type": "number"
         },
         "weight": {
          "type": "n
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "grade": "strong",
  "score": 72.4,
  "source": "deterministic in-process finance calculator; no upstream API",
  "drivers": [
   {
    "name": "break_even",
    "note": "16.1 months to break even",
    "score": 67.8,
    "weight": 0.25
   }
  ],
  "metrics": {
   "monthly_savings": 384.24,
   "break_even_months": 16.1,
   "new_monthly_payment": 2576.9,
   "current_monthly_payment": 2961.14
  },
  "warnings": [],
  "calculator": "refinance-analysis-calculator",
  "recommendation": "Proceed with standard diligence and covenant checks."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/refi-break-even-calculator-6d22055e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentutility.ai](https://www.zero.xyz/host/x402.agentutility.ai/llms.txt)