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/152` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform 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 the same $0.02/request price point.
The specific functionality behind `/api/v1/transfers/152` is not documented beyond the label "Premium API Access." The crawled docs, pricing, and API pages all rendered only a "Connect wallet" prompt with no additional documentation. There is no OpenAPI spec, no request/response schema, and no usage examples available. The endpoint is live and responds with a well-formed x402 challenge, but the actual payload it returns after payment is unknown.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 protocol integrations against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless API access with crypto micropayments
- —Low-volume consumers who prefer pay-per-call over subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who need bulk pricing or rate-limit guarantees
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/152 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is zero documentation on what the endpoint actually does or returns. No OpenAPI spec, no request/response examples, and the docs/pricing/API pages are all behind a wallet-connect gate. The listing is effectively a stub with confirmed liveness.
Warnings
- —No documentation available — docs, pricing, and API pages all render only 'Connect wallet' with no content.
- —No OpenAPI or schema describing request parameters or response format for /api/v1/transfers/152.
- —The specific functionality of 'Premium API Access' at this endpoint path is completely undocumented.
- —Cannot verify what data or service is returned after successful payment.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base network.https://lowpaymentfee.com/api/v1/transfers/152
- —The platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/request.https://lowpaymentfee.com
- —The platform advertises no API keys, no rate limits, instant access, and Base network settlement.https://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base network.https://lowpaymentfee.com/api/v1/transfers/152