Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/transfers/183` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an x402 payment header to each request.
The broader lowpaymentfee.com site offers endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at $0.02 per request. However, the specific endpoint probed here (`/api/v1/transfers/183`) does not clearly map to any of those advertised categories, and its actual functionality is not documented beyond the generic "Premium API Access" label.
Documentation is extremely thin — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what this particular endpoint returns. The endpoint is live and responds with a valid x402 challenge, but the lack of documentation makes it impossible to confirm what data or service it provides.
Capabilities
Use cases
- —Accessing pay-per-request API endpoints without API key management
- —Making micropayment-gated API calls settled in USDC on Base
- —Programmatic agent-to-service payments via x402 protocol
Fit
Best for
- —Developers wanting keyless, pay-as-you-go API access
- —Agents that can settle x402 USDC payments on Base
- —Use cases requiring low-friction per-call billing
Not for
- —Users needing detailed API documentation or schemas before purchasing
- —Applications requiring guaranteed SLAs or support contracts
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/183 \
-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 no documentation, no OpenAPI schema, no request/response examples, and the endpoint's actual functionality ('Premium API Access' on a /transfers/ path) is completely undocumented. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet' with no content
- —The endpoint path /api/v1/transfers/183 does not correspond to any of the advertised API categories on the homepage
- —No OpenAPI schema or request/response examples are available
- —Actual functionality of this specific endpoint is unknown beyond the generic 'Premium API Access' label
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/transfers/183
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transfers/183
- —Documentation pages (/docs, /api, /pricing, /README) render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs