Pay-per-call API platform on Base network via x402 — $0.02/request, no API keys required.
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 data, and infrastructure utilities. All endpoints are priced at $0.02 per request, paid in USDC on the Base network using the x402 payment protocol. No API keys, rate limits, or upfront commitments are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The specific endpoint at `/api/v1/charges/24` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0.02 USDC, i.e., $0.02) on Base. 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).
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 detailed documentation for any endpoint. The endpoint is confirmed live via a valid 402 challenge, but the actual behavior behind the paywall is unknown.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data such as token quotes, exchange rates, and gas estimates
- —Running utility operations like geocoding, validation, and data conversion on a per-call payment basis
- —Exporting analytics data and generating insights reports
Fit
Best for
- —Agents or developers who want instant API access without signup or key provisioning
- —Low-volume or bursty workloads where per-request pricing is more efficient than subscriptions
- —x402-compatible agents that can settle USDC micropayments on Base
Not for
- —High-volume production workloads where $0.02/request adds up significantly
- —Users who need detailed API documentation, schemas, or SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/24 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty beyond a wallet-connect prompt. The actual functionality behind 'Premium API Access' at /api/v1/charges/24 is unspecified. This is effectively a stub listing.
Warnings
- —No API documentation available — all doc pages render only 'Connect wallet' with no content
- —No OpenAPI or JSON schema provided for any endpoint
- —The specific purpose of /api/v1/charges/24 ('Premium API Access') is unclear and not described anywhere
- —No request or response examples are available; actual endpoint behavior behind the paywall is unknown
- —The broad catalog of advertised endpoints (AI, finance, analytics, etc.) cannot be verified for functionality
Citations
- —All endpoints priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —Payment is in USDC on the Base network via x402 protocolhttps://lowpaymentfee.com
- —402 challenge requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/charges/24
- —Categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com