Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad set of 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 priced at $0.02 per request, settled in USDC on the Base network via the x402 payment protocol.
The specific endpoint at `/api/v2/users` is listed as "Premium API Access." Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the `exact` scheme with a 300-second timeout. No API keys or rate limits are required — callers simply attach an X-PAYMENT header to each request.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional content. There is no OpenAPI schema, no request/response examples, and no description of what the `/api/v2/users` endpoint actually returns. The platform's landing page confirms the pricing model and lists available endpoints, but provides no technical detail about request formats or response structures.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification) without API key management
- —Fetching real-time crypto gas estimates or token price quotes via micropayment
- —Geocoding or data validation as a utility service paid per call
- —Exporting analytics data or generating insights on a pay-as-you-go basis
Fit
Best for
- —AI agents that need keyless, pay-per-call access to diverse utility endpoints
- —Developers prototyping with low-cost, no-commitment API access on Base
- —Web3-native applications that already hold USDC on Base
Not for
- —High-volume production workloads where $0.02/request adds up quickly without bulk discounts
- —Users who need detailed API documentation, schemas, or SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v2/users \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, and no documentation beyond a landing page listing. The purpose of the /api/v2/users endpoint specifically is undocumented. Effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content.
- —The /api/v2/users endpoint has no description of what it does, what input it expects, or what it returns.
- —No OpenAPI schema or request/response examples are provided anywhere.
- —The broader platform lists many endpoints but none have documented schemas or usage guides.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v2/users
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet' with no additional contenthttps://lowpaymentfee.com/docs