Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a collection of endpoints spanning data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are pay-per-request using the x402 protocol, settling payments in USDC on the Base network. 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/transfers/163` is listed as "Premium API Access" and requires a maximum of 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises a uniform $0.02 price across all its endpoints. The broader catalog includes sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, gas estimates, geocoding, validation, conversion, and data export endpoints.
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 detailed description of what the `/api/v1/transfers/163` endpoint actually returns. The x402 challenge is live and well-formed, confirming the endpoint is operational, but the lack of documentation makes it difficult to know what data or functionality this specific endpoint provides.
Capabilities
Use cases
- —Accessing AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time finance data (prices, exchange rates, gas estimates) with per-call USDC payments
- —Running utility operations (geocoding, validation, conversion) on a pay-as-you-go basis
- —Integrating agent-purchasable API calls into autonomous workflows via x402
Fit
Best for
- —Developers wanting zero-signup, pay-per-use API access
- —AI agents that can settle payments autonomously via x402 on Base
- —Projects needing low-cost micropayment-gated endpoints without rate limits
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscription plans
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/163 \
-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. However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty beyond a wallet-connect prompt. The specific purpose of /api/v1/transfers/163 is unclear. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all show only 'Connect wallet'
- —No OpenAPI or schema definition found for any endpoint
- —The specific function of /api/v1/transfers/163 ('Premium API Access') is not described anywhere
- —No request or response examples available to verify endpoint behavior
- —Cannot confirm what data or service this specific endpoint actually provides
Citations
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge for /api/v1/transfers/163 requires maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transfers/163
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com