Loan amortization schedule API, pay-per-call at $0.02 via USDC on Base.
What it does
This endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 71 in this URL pattern). It is part of a broader platform offering various pay-per-request APIs spanning data analytics, AI/ML inference, finance, and utility services — all settled via the x402 protocol using USDC on the Base network.
The endpoint accepts POST requests and is gated behind an x402 payment challenge. The maximum amount required per call is 20,000 base units of USDC (which uses 6 decimals), equating to $0.02 per request. Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 on Base, with a timeout of 300 seconds. The response MIME type is application/json.
Documentation on the site is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The loan schedule endpoint's input parameters (e.g., loan terms, interest rate, principal) and output fields are unknown. The platform advertises no API keys, no rate limits, and instant access, but specifics about the loan schedule functionality must be inferred from the endpoint path alone.
Capabilities
Use cases
- —Generating an amortization schedule for a loan to see payment breakdowns over time
- —Integrating loan schedule data into a financial planning application
- —Agents autonomously fetching loan repayment details without API key management
Fit
Best for
- —Developers needing quick, keyless access to loan schedule calculations
- —AI agents that can settle micropayments on Base for financial data
- —Applications requiring pay-as-you-go loan amortization without subscriptions
Not for
- —Users who need detailed API documentation or schema guarantees before integrating
- —High-volume batch loan calculations where per-request pricing may add up
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/71/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (returns a valid 402 challenge), but there is zero documentation on request parameters, response schema, or what loan ID 71 represents. No OpenAPI spec, no examples, and all doc pages are empty. The listing is effectively a stub with only pricing and protocol details confirmed.
Warnings
- —No API documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content
- —No request or response schema documented; input parameters for the loan schedule are unknown
- —The endpoint path hardcodes loan ID 71; it is unclear whether other loan IDs are supported or how loans are created
- —The platform lists many API categories (AI, analytics, finance, utilities) but provides no evidence any return meaningful data
Citations
- —The endpoint returns a 402 challenge requiring USDC payment on Base network with maxAmountRequired of 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/loans/71/schedule
- —The platform advertises $0.02 per request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Payment is to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 (USD Coin)https://lowpaymentfee.com/api/v1/loans/71/schedule