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 70 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 returns a 402 challenge requesting payment of up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per request. Payment is made via the x402 "exact" scheme to a specified wallet address. The response MIME type is application/json. The endpoint accepts POST requests and is marked as discoverable.
Documentation beyond the landing page 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 examples of what parameters the POST body should contain or what the schedule response looks like. The loan ID (70) is hardcoded in the URL path, and it is unclear whether other loan IDs are available or how loans are created. The platform advertises $0.02 per request with no API keys, no rate limits, and instant access.
Capabilities
Use cases
- —Retrieve a detailed amortization schedule for a loan showing principal and interest breakdowns per period
- —Integrate loan schedule data into financial planning or lending applications
- —Automate loan payment calculations without maintaining a subscription or API key
Fit
Best for
- —Agents or apps needing on-demand loan schedule data without signup
- —Developers wanting crypto-native pay-per-call financial APIs
- —Quick prototyping of lending or financial planning tools
Not for
- —Production use requiring documented request/response schemas and SLAs
- —Bulk or high-volume loan origination workflows (no documented batch support)
- —Users who cannot pay with USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/70/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is virtually no documentation: no OpenAPI spec, no request/response schema, no examples, and the docs pages are empty. The loan ID is hardcoded in the path with no explanation. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request body format and response structure are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —Loan ID 70 is hardcoded in the endpoint path; it is unclear how to access other loans or create new ones
- —The specific /loans/70/schedule endpoint is not listed on the provider's landing page among advertised APIs
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/70/schedule
- —Platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/loans/70/schedule