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 at `/api/v1/transactions/98` is labeled "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 $0.02 per request.
Documentation is extremely sparse. The /docs, /api, /pricing, 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/98` endpoint actually returns. The endpoint is live (402 challenge confirmed), but without documentation it is unclear what data or functionality this specific route provides.
Capabilities
Use cases
- —Accessing premium API data without requiring API key registration
- —Making one-off paid API calls settled in USDC on Base
- —Agent-driven programmatic access to various utility and data endpoints
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —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 pricing models
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/98 \
-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 the /api/v1/transactions/98 endpoint actually returns. 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 parameters or response format
- —The specific purpose of /api/v1/transactions/98 ('Premium API Access') is not explained anywhere
- —Cannot verify what data or functionality this endpoint provides
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/transactions/98
- —The platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —Platform advertises no API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/98