Pay-per-call API platform on Base network via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, 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 subscription commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/264` 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 advertises additional 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. However, documentation beyond the landing page is extremely sparse; the docs, API, pricing, and README pages all returned only a "Connect wallet" prompt with no substantive content.
Because there is no OpenAPI schema, no request/response examples, and no documentation describing what this particular endpoint actually returns or what input it expects, it is difficult to assess the real functionality behind the "Premium API Access" label. The x402 challenge is live and well-formed, confirming the endpoint is operational and accepts POST requests with USDC payment on Base.
Capabilities
Use cases
- —Accessing premium API data without managing API keys or subscriptions
- —Making one-off paid API calls settled in USDC on Base
- —Agent-driven workflows that need instant, keyless API access with crypto payment
Fit
Best for
- —Developers who want zero-friction, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —Anyone without USDC on Base or unfamiliar with x402 payment flows
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/264 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC). However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty stubs ('Connect wallet'). The actual functionality behind 'Premium API Access' is undefined, making this effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all return only 'Connect wallet' with no content.
- —The purpose and expected input/output of /api/v1/transactions/264 ('Premium API Access') is not described anywhere.
- —No OpenAPI or JSON schema provided for request or response bodies.
- —Cannot verify what data or service this endpoint actually provides.
Citations
- —The endpoint returns a 402 x402 challenge requiring 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/264
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/264