Pay-per-request API platform on Base via x402 — $0.02/call, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are pay-per-request using USDC on the Base network, settled via the x402 protocol. There are no API keys, no rate limits, and no subscription commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/products/14` is listed as "Premium API Access" and requires a maximum of 20,000 base units of USDC (0.02 USDC, i.e., $0.02) per call. The platform also exposes endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. Payment is made to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` on Base.
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 description of what the `/api/v1/products/14` endpoint actually returns. The endpoint is live (returns a valid 402 challenge), but without documentation it is unclear what data or functionality "Premium API Access" provides beyond its name.
Capabilities
Use cases
- —Agents that need on-demand API access without managing API keys or subscriptions
- —Paying per-request for analytics, AI inference, or financial data via USDC on Base
- —Integrating low-cost utility endpoints (geocoding, validation, conversion) into automated workflows
Fit
Best for
- —Developers and agents wanting frictionless, keyless API access via crypto micropayments
- —Low-volume or bursty workloads where per-call pricing is more economical than subscriptions
- —Web3-native applications already operating on the Base network
Not for
- —High-volume production workloads needing guaranteed SLAs and detailed documentation
- —Users without access to USDC on the Base network
- —Applications requiring well-documented request/response schemas before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/14 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts payments. However, documentation is effectively nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI schema, no request/response examples, and no description of what 'Premium API Access' actually returns. The listing is a stub with pricing info only.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all render only 'Connect wallet' with no usable content.
- —No OpenAPI or schema available — request and response formats are unknown.
- —The name 'Premium API Access' is generic; it is unclear what data or functionality this specific endpoint provides.
- —No examples of successful responses are available anywhere in the crawled material.
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/products/14
- —USDC contract address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/products/14
- —All 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