Pay-per-call API platform on Base with USDC payments via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are pay-per-request using USDC on the Base network, settled via the x402 protocol. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/policies/76` is listed as "Premium API Access" and requires a maximum of 20,000 base units of USDC (0.02 USDC, i.e., $0.02) per call. The platform also hosts endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point.
Documentation 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 schema, no request/response examples, and no description of what the "Premium API Access" policy/76 endpoint actually returns. Without additional documentation it is unclear what data or functionality this specific endpoint provides.
Capabilities
Use cases
- —Accessing premium API data without needing to register or manage API keys
- —Making one-off API calls with instant USDC micropayments on Base
- —Integrating pay-per-request endpoints into autonomous agent workflows
Fit
Best for
- —Developers who want zero-friction API access without subscriptions
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost, on-demand API calls without rate limits
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who prefer flat-rate or subscription pricing
- —Developers without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/policies/76 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts USDC payments on Base at $0.02/request. However, there is no OpenAPI schema, no request/response examples, and no documentation beyond a landing page listing endpoint names. The specific purpose of /api/v1/policies/76 ('Premium API Access') is entirely undocumented.
Warnings
- —No OpenAPI or schema documentation available — all docs/pricing/README pages render only 'Connect wallet'
- —The purpose and expected input/output of /api/v1/policies/76 is completely undocumented
- —The platform lists many endpoints but provides no technical details for any of them
Citations
- —The endpoint returns a 402 x402 challenge requiring USDC payment of 20000 base units (0.02 USDC) on Base networkhttps://lowpaymentfee.com/api/v1/policies/76
- —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/policies/76
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com