Pay-per-call API platform on Base network 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/payments/380` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) 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 listed at the same $0.02/request price point.
However, documentation is extremely thin. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI schema, no request/response examples, and no description of what the `/api/v1/payments/380` endpoint specifically returns. The endpoint path (`/payments/380`) does not clearly map to any of the advertised API categories, making its actual functionality unclear.
Capabilities
Use cases
- —Accessing pay-per-request API endpoints without managing API keys or subscriptions
- —Making micropayment-gated API calls settled in USDC on Base
- —Programmatic access to data, AI, finance, or utility endpoints via x402 protocol
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Projects already operating on the Base L2 network with USDC
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —Production systems requiring well-documented request/response schemas
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/380 \
-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 on Base at $0.02/request. However, there is no OpenAPI schema, no request/response examples, no documentation beyond a wallet-connect prompt, and the specific functionality of /api/v1/payments/380 is not described anywhere. This is effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format
- —The endpoint path /api/v1/payments/380 does not correspond to any of the advertised API categories, so its actual functionality is unknown
- —No request or response examples available anywhere in the crawl
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/payments/380
- —The platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —The platform advertises no API keys, no rate limits, instant access, and Base network settlementhttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs