Loan amortization schedule API, pay-per-request via x402 on Base (USDC).
What it does
This endpoint at lowpaymentfee.com returns a loan amortization schedule for a specific loan (loan ID 27 in the URL path). It is part of a broader platform offering pay-per-call APIs across data analytics, AI/ML, finance, and utility categories, all settled via the x402 protocol on the Base network using USDC.
The endpoint is live and responds with a 402 Payment Required challenge, requesting an x402 payment of up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per request. Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 on Base. The endpoint accepts POST requests and returns application/json. No API keys or rate limits are advertised; access is gated purely by micropayment.
Documentation is extremely sparse. The crawled docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no description of request parameters (e.g., how to specify loan terms, interest rate, or principal), and no example responses. The loan ID 27 is hardcoded in the URL, and it is unclear whether other loan IDs are supported or how loans are created. The platform's landing page lists many endpoint categories at $0.02/request, but this specific loans/schedule endpoint is not listed among them, making its purpose and data model uncertain.
Capabilities
Use cases
- —Retrieving a loan amortization schedule showing periodic payment breakdowns
- —Integrating loan payment calculations into financial planning tools
- —Agent-driven loan analysis workflows that pay per query
Fit
Best for
- —Developers needing on-demand loan schedule data without API key management
- —AI agents that can settle x402 micropayments on Base
- —Applications requiring pay-as-you-go financial calculation endpoints
Not for
- —Users who need detailed API documentation or request/response schemas 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/27/schedule \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no request/response examples, and the specific loans/schedule endpoint is not even listed on the provider's own landing page. The loan ID is hardcoded with no explanation. This is effectively a stub listing.
Warnings
- —No API documentation available — docs, pricing, and README pages all render only a wallet-connect prompt
- —No request parameter schema: it is unknown what POST body fields are expected
- —No response schema or example: the structure of the amortization schedule output is unknown
- —This specific endpoint (/api/v1/loans/27/schedule) is not listed among the provider's advertised APIs
- —Loan ID 27 is hardcoded in the path with no explanation of how loans are created or whether other IDs work
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/27/schedule
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/27/schedule