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 4 in the URL path). It is part of a broader platform offering pay-per-request APIs across data analytics, AI/ML, finance, and utility categories, 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 is extremely sparse. The crawled docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what input parameters the POST body expects or what fields the schedule response contains. The loan ID is embedded in the URL path, suggesting the endpoint may be parameterized per loan. Without further documentation it is unclear whether callers can specify loan terms (principal, rate, duration) in the request body or whether loan 4 is a fixed demo resource.
Capabilities
Use cases
- —Generating an amortization schedule for a loan to see principal and interest breakdowns per period
- —Integrating loan schedule data into a fintech application without managing API keys
- —Agent-driven financial planning that needs on-demand loan payment breakdowns
Fit
Best for
- —Developers needing quick, keyless access to loan schedule calculations
- —AI agents that need to fetch structured loan amortization data programmatically
- —Pay-as-you-go financial microservices with no subscription commitment
Not for
- —Bulk or high-volume loan processing where per-call costs add up
- —Users who need detailed documentation or guaranteed SLAs before integrating
- —Scenarios requiring customizable loan parameters if the endpoint only serves a fixed loan ID
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/4/schedule \
-H "X-PAYMENT: <x402_payment_token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages returned only a wallet-connect stub. The specific purpose of this endpoint (loan schedule for loan ID 4) is only inferable from the URL path; no details on input parameters or response shape are available.
Warnings
- —No documentation available — all doc pages return only a 'Connect wallet' prompt with no content.
- —No OpenAPI or request/response schema provided; input parameters and response structure are unknown.
- —The loan ID (4) is hardcoded in the URL path; it is unclear if other loan IDs are supported or how loans are created.
- —The endpoint is listed under 'Premium API Access' but the homepage does not list this specific loans endpoint among its advertised APIs.
Citations
- —The endpoint returns HTTP 402 with an x402 challenge requiring 20,000 base units of USDC on Base (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913).https://lowpaymentfee.com/api/v1/loans/4/schedule
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on the Base network.https://lowpaymentfee.com
- —USDC uses 6 decimals, so 20,000 base units equals $0.02.https://lowpaymentfee.com