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 catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/keys/97` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — no API keys, accounts, or subscriptions are required; callers attach an X-PAYMENT header with a signed USDC payment to each request.
The wider platform advertises four endpoint 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 listed endpoints share the same $0.02/request pricing. The platform claims no rate limits and instant access.
Important caveat: the specific endpoint probed (`/api/v1/keys/97`) does not clearly map to any of the named API categories on the landing page. Its purpose — "Premium API Access" — is vague and undocumented. There is no OpenAPI schema, no request/response examples, and the /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no additional documentation. Prospective callers should treat this as a minimally documented endpoint until the provider publishes schemas or usage guides.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification, embeddings) without managing API keys
- —Fetching real-time financial data such as token quotes, exchange rates, or gas estimates via micropayment
- —Running geocoding or data validation calls from autonomous workflows that settle in USDC on Base
Fit
Best for
- —AI agents needing keyless, pay-per-call access to multiple utility endpoints
- —Developers who want to avoid subscription commitments and pay only per request
- —Web3-native applications that can sign USDC payments on Base
Not for
- —High-volume batch workloads where per-request pricing at $0.02 adds up quickly
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
- —Callers without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/97 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, and the endpoint name 'Premium API Access' is vague. Documentation pages (/api, /pricing, /README) returned no useful content. The actual functionality behind /api/v1/keys/97 is unknown.
Warnings
- —No OpenAPI or JSON schema available for this endpoint
- —The endpoint path /api/v1/keys/97 does not match any of the named APIs on the landing page — its actual functionality is unclear
- —All documentation pages (/api, /pricing, /README) returned only 'Connect wallet' with no technical content
- —No request or response examples are available anywhere in the crawled material
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (asset 0x8335…) on Base networkhttps://lowpaymentfee.com/api/v1/keys/97
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com