Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints across data analytics, AI/ML inference, finance/Web3, and utility services. All endpoints are priced at $0.02 per request, paid in USDC on the Base network, with no API keys, no rate limits, and no subscriptions required. The specific endpoint at /api/v1/payments/325 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 categories including 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 (geocoding, validation, conversion, generation). However, the crawled documentation pages (/docs, /api, /pricing, /README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior, input/output schemas, and data sources behind these endpoints remain undocumented.
The endpoint is live and responds with a valid x402 challenge. Payment settles on Base via USDC (contract 0x8335…2913) to address 0x1A2B…85F3. The POST method is specified in the outputSchema. Without documentation or example responses, it is unclear what payload this specific endpoint expects or returns.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Paying per-call for analytics, AI inference, or financial data via USDC on Base
- —Programmatic access to geocoding, validation, or conversion utilities with crypto micropayments
Fit
Best for
- —Developers or agents who want zero-signup, pay-as-you-go API access
- —Use cases requiring small, infrequent API calls without subscription overhead
- —x402-compatible agent wallets on the Base network
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where per-request pricing at $0.02 may add up
- —Users without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/325 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts USDC payments on Base. However, all documentation pages are empty (just 'Connect wallet'), there is no OpenAPI spec, no input/output schema beyond the method, and the purpose of /api/v1/payments/325 specifically is unclear. The platform lists many endpoints but provides no details on what data they actually return.
Warnings
- —All documentation pages (/docs, /api, /pricing, /README) returned no useful content — only 'Connect wallet' prompts.
- —No OpenAPI or schema available; input and output formats for this endpoint are unknown.
- —The specific endpoint /api/v1/payments/325 is not listed among the advertised API catalog — its purpose is unclear.
- —No example requests or responses are available anywhere in the crawled material.
Citations
- —Endpoint returns a valid x402 402 challenge requesting up to 20,000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/325
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/325
- —Categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com