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 76 in the URL path). It is part of a broader platform offering dozens of pay-per-call APIs spanning data analytics, AI/ML inference, finance, crypto, and utility services — all gated behind the x402 payment protocol on the Base network using USDC.
The specific endpoint `/api/v1/loans/76/schedule` accepts POST requests and returns JSON. The x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 per request (USDC uses 6 decimals). The platform's landing page confirms a flat $0.02/request pricing model across all endpoints, with no API keys, no rate limits, and no minimum commitments required.
Documentation is extremely sparse — the /docs, /pricing, /api, 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 fields the POST body should contain or what the schedule response looks like. The endpoint is live (returns a proper 402 challenge), but without documentation it is difficult to know what input parameters are expected or what the output format is. The loan ID (76) is hardcoded in the URL, suggesting either a demo/sample loan or that callers would substitute their own loan ID.
Capabilities
Use cases
- —Retrieve a detailed amortization schedule for a loan showing principal and interest breakdowns per period
- —Integrate loan schedule data into a financial planning application without managing API keys
- —Programmatically calculate or verify loan payment schedules using a pay-per-call model
Fit
Best for
- —Agents or apps needing on-demand loan amortization data without subscription overhead
- —Developers prototyping financial tools who want instant API access with crypto micropayments
- —Automated financial workflows that need per-call billing on Base L2
Not for
- —Users who need comprehensive loan origination or servicing beyond schedule generation
- —Anyone requiring detailed API documentation or guaranteed SLAs before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/loans/76/schedule \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02/request in USDC on Base). However, there is no OpenAPI spec, no request/response schema, and all documentation pages are empty beyond a wallet connect prompt. The specific endpoint path (loans/76/schedule) is not mentioned anywhere on the site's landing page, making its purpose inferrable only from the URL structure. This is effectively a stub listing.
Warnings
- —No API documentation available — /docs, /pricing, /api, and /README pages are all empty
- —No request body schema or response schema documented; input parameters are unknown
- —The loan ID 76 is hardcoded in the endpoint URL; unclear if this is a demo or how to specify other loans
- —This specific endpoint (/api/v1/loans/76/schedule) is not listed on the provider's landing page among their advertised APIs
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/loans/76/schedule
- —Platform pricing is $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/loans/76/schedule