Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.
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/charges/184` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0.02 USD) 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 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 priced at $0.02 per request.
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 schema, no request/response examples, and no description of what the `/api/v1/charges/184` endpoint actually returns. The endpoint is live (402 challenge confirmed), but without documentation it is unclear what data or functionality "Premium API Access" provides.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to analytics, AI, finance, or utility endpoints
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments autonomously
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who want bulk pricing or subscription discounts
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/184 \
-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 virtually no documentation: no OpenAPI schema, no request/response examples, and no explanation of what 'Premium API Access' actually returns. The docs, pricing, API, and README pages are all blank beyond a wallet-connect prompt. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet' with no content.
- —No OpenAPI or schema describing request parameters or response format for /api/v1/charges/184.
- —It is unclear what 'Premium API Access' at /api/v1/charges/184 actually provides — the endpoint name is generic.
- —The broader platform lists many endpoint categories (AI, finance, analytics, infrastructure) but none have documented schemas or examples.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base network.https://lowpaymentfee.com/api/v1/charges/184
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access.https://lowpaymentfee.com
- —The platform offers endpoints in Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com
- —The /docs, /pricing, /api, and /README pages render only a 'Connect wallet' prompt with no further documentation.https://lowpaymentfee.com/docs