# Loan Amortization Schedule Calculator

> Loan Amortization Schedule Calculator is a paid API for AI agents from api.24klabs.ai, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-13).

Generates a full amortization schedule from loan principal, APR, and term, including monthly payment, per-period principal/interest breakdown, running balance, total interest, and payoff date.

## Facts

- Endpoint: POST https://api.24klabs.ai/api/loan-amortization-schedule
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/loan-amortization-schedule-calculator-424fecf7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Gm222YA57pNBAh-ehQ-B5

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 loan-amortization-schedule-calculator-424fecf7 -d '<json body>'
```

Example prompt: Can you generate a full amortization schedule for a $350,000 mortgage at 6.75% APR over 30 years, with an extra $200 payment each month? I want to see the monthly breakdown of principal and interest, running balance, total interest paid, and when the loan will be paid off.

## When to prefer this

Choose this endpoint when you need a complete, period-by-period amortization breakdown rather than just a monthly payment estimate. Ideal for mortgage planning, car loan analysis, personal loan comparisons, or any scenario where a user wants to visualize how their balance decreases over time, understand the total interest cost, or model the impact of extra payments on payoff date.

## Known failure modes

- Invalid APR (negative or zero) returns validation error
- Loan term of zero or negative months returns error
- Principal amount of zero or negative returns error
- Missing required fields (principal, APR, or term) returns 400-level error
- Extremely large principal or term values may cause computation edge cases

## How this service works

Full amortization table from principal, APR and term (plus optional extra payment): monthly payment, per-period principal/interest split, running balance, total interest, payoff date.

## Output

Returns a complete amortization table with one row per payment period containing the payment number, payment amount, principal portion, interest portion, and remaining balance. Also includes summary fields: total interest paid over the life of the loan, total amount paid, and projected payoff date. Optional extra payment scenarios adjust the schedule accordingly.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "apr": {
   "type": "number"
  },
  "principal": {
   "type": "number"
  },
  "start_date": {
   "type": "string"
  },
  "term_years": {
   "type": "number"
  },
  "extra_payment": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "payoff_months": 300,
  "total_interest": 296697,
  "monthly_payment": 1580.17
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/loan-amortization-schedule-calculator-424fecf7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.24klabs.ai](https://www.zero.xyz/host/api.24klabs.ai/llms.txt)