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/272` 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 $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/272` endpoint actually returns. The endpoint is live (402 challenge confirmed), but without documentation it is unclear what data or functionality this specific transaction endpoint provides.
Capabilities
Use cases
- —Programmatic access to API endpoints without managing API keys or subscriptions
- —Agent-driven workflows that need on-demand paid API calls settled in USDC on Base
- —Exploring x402 protocol integrations for pay-per-use services
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, pay-as-you-go API access on Base
- —Low-volume consumers who want per-request billing with no commitments
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —High-volume production workloads where $0.02/request adds up quickly
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/272 \
-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 there is essentially no documentation: no OpenAPI schema, no request/response examples, no description of what the endpoint returns. The docs pages are empty beyond a wallet-connect prompt. The specific endpoint path (/api/v1/transactions/272) is not listed on the homepage, making its purpose unclear.
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 specific endpoint /api/v1/transactions/272 is not listed among the advertised APIs on the homepage
- —Purpose and return data of this endpoint are unknown — 'Premium API Access' is the only description
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/272
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transactions/272
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com