# QuantOracle Fixed-Income Amortization Calculator

> QuantOracle Fixed-Income Amortization Calculator is a paid API for AI agents from api.quantoracle.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Computes a full loan amortization schedule with optional extra payments, returning month-by-month balances, interest, principal breakdown, and total interest saved

## Facts

- Endpoint: POST https://api.quantoracle.dev/v1/fixed-income/amortization
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-quantoracle-dev-aff98a96
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_z-x6NV-72mFI_eSdcH2e-

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 api-quantoracle-dev-aff98a96 -d '<json body>'
```

Example prompt: Can you generate a full amortization schedule for a $350,000 mortgage at 6.5% annual interest over 30 years, with an extra $200 payment each month, so I can see how much interest I save and when it'll be paid off?

## When to prefer this

Use this endpoint when you need a precise, full amortization schedule for a fixed-rate loan, especially when modeling the impact of extra payments on total interest and payoff timeline. Prefer over generic financial calculators when you need a machine-readable month-by-month schedule array for further analysis or display.

## Known failure modes

- Missing required fields (principal, annual_rate, years) returns a 400 validation error
- Negative or zero principal/rate/years results in computation error
- Extremely large principal or very long terms may produce overflow or timeout
- Invalid data types (e.g. string instead of number) return a 422 unprocessable entity

## How this service works

QuantOracle: fixed-income/amortization

## Output

Returns a complete month-by-month amortization schedule including each month's payment amount, remaining balance, interest portion, and principal portion; plus summary fields for total months to payoff, total interest paid, interest saved versus no extra payments, and the base monthly payment with and without extra contributions. Response time is typically under 20ms.

## Example request

```json
{
 "years": 30,
 "principal": 350000,
 "annual_rate": 6.5,
 "extra_payment": 200
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "years": {
   "type": "integer",
   "title": "Years",
   "maximum": 50,
   "minimum": 1,
   "description": "Loan term in years"
  },
  "principal": {
   "type": "number",
   "title": "Principal",
   "description": "Loan principal amount",
   "exclusiveMinimum": 0
  },
  "annual_rate": {
   "type": "number",
   "title": "Annual Rate",
   "minimum": 0,
   "description": "Annual interest rate"
  },
  "extra_payment": {
   "type": "number",
   "title": "Extra Payment",
   "default": 0,
   "description": "Extra payment per period"
  }
 }
}
```

## More

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