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/transactions/372` 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 uniformly 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/transactions/372` endpoint actually returns. The endpoint is live (402 challenge confirmed), but without documentation it is unclear what input the POST body expects or what data it provides.
Capabilities
Use cases
- —Accessing premium data or transaction information via a single USDC micropayment
- —Programmatic pay-per-call API consumption without managing API keys or subscriptions
- —Agent-driven workflows that need on-demand API access settled in USDC on Base
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents with x402-compatible payment capabilities
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Applications requiring free or subscription-based access models
- —Users who need fiat-only payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/372 \
-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 documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI schema, no request/response examples, and no explanation of what this specific endpoint does beyond the generic label 'Premium API Access'. The listing is effectively a stub.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README pages all render only 'Connect wallet'
- —No OpenAPI or schema describing request body or response format for this endpoint
- —The endpoint name 'Premium API Access' and path '/api/v1/transactions/372' give no clear indication of what data or service is provided
- —Cannot verify what the endpoint actually returns upon successful payment
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/372
- —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 & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages (/docs, /pricing, /api, /README) render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs