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/payments/98` is listed as "Premium API Access" and charges 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 uniformly priced at $0.02 per request.
This particular endpoint (`/api/v1/payments/98`) is confirmed live, returning a proper 402 challenge with x402 version 1. The payment is settled on Base using USDC (contract `0x8335...2913`). However, the crawled documentation pages (docs, api, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so the actual functionality behind this specific endpoint remains unclear. The endpoint's description is simply "Premium API Access" with no further detail on what data or service it returns.
Capabilities
Use cases
- —Accessing premium API endpoints without traditional API key registration
- —Making micropayment-gated API calls settled in USDC on Base
- —Integrating pay-per-use services into agent workflows via x402 protocol
Fit
Best for
- —Developers who want instant API access without signup or API keys
- —Agent systems that can handle x402 payment challenges natively
- —Users comfortable paying in USDC on the Base L2 network
Not for
- —Users who need detailed API documentation before integrating
- —Anyone requiring fiat-only payment methods with no crypto involvement
Quick start
# The endpoint returns 402 with an x402 challenge.
# Attach a valid X-PAYMENT header (x402 v1, USDC on Base) to POST:
curl -X POST https://lowpaymentfee.com/api/v1/payments/98 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and no explanation of what "Premium API Access" actually returns. The docs, pricing, and README pages are all empty (just 'Connect wallet'). The listing is effectively a stub.
Warnings
- —No documentation available — all doc pages return only 'Connect wallet' with no content
- —The actual functionality behind 'Premium API Access' at /api/v1/payments/98 is completely undocumented
- —No OpenAPI schema or request/response examples are provided
- —No information on what data or service this specific endpoint delivers
Citations
- —The endpoint returns a 402 challenge with x402 version 1, accepting USDC on Base with maxAmountRequired of 20000 base units ($0.02)https://lowpaymentfee.com/api/v1/payments/98
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/98
- —The platform offers endpoints in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com