Pay-per-call API suite on Base (USDC) covering AI, analytics, finance, and utilities at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general infrastructure utilities. Every endpoint is priced at $0.02 per request, payable in USDC on the Base network via the x402 protocol — no API keys, no rate limits, and no upfront commitments required.
The specific endpoint at `/api/v1/messages/11` is listed as "Premium API Access." Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335… on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts HTTP POST requests and returns `application/json`. Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout.
The broader platform advertises additional endpoints including 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 per-call price point. However, no OpenAPI schema, detailed request/response documentation, or usage examples were found in the crawl. The `/api`, `/pricing`, and `/README` pages all returned only a "Connect wallet" prompt with no substantive content. Without documentation it is unclear what request bodies these endpoints expect or what response shapes they return.
Capabilities
Use cases
- —Running one-off AI inference tasks (sentiment, summarization, classification) without managing API keys
- —Fetching real-time crypto token quotes or gas estimates via a single paid call
- —Geocoding addresses or validating data on demand with per-call billing
- —Exporting analytics data or generating insights without subscription commitments
Fit
Best for
- —Agents or bots that need keyless, pay-as-you-go API access
- —Low-volume or sporadic callers who want to avoid subscriptions
- —Developers experimenting with x402 protocol payments on Base
Not for
- —High-volume production workloads where $0.02/call adds up quickly
- —Users who need detailed API documentation or SLAs before integrating
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/11 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02/call in USDC on Base). However, there is no OpenAPI schema, no request/response documentation, no examples, and the specific endpoint's purpose ("Premium API Access" at /api/v1/messages/11) is unexplained. The crawl yielded only a landing page listing endpoints and empty wallet-connect pages.
Warnings
- —No OpenAPI or schema documentation found for any endpoint
- —The purpose of /api/v1/messages/11 specifically is unclear — 'Premium API Access' is generic
- —All sub-pages (/api, /pricing, /README) returned only 'Connect wallet' with no useful content
- —No request body format or response schema is documented anywhere in the crawl
- —The breadth of advertised capabilities (AI, finance, geocoding, etc.) cannot be verified without docs
Citations
- —Endpoint returns 402 with x402 challenge advertising 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/messages/11
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/messages/11
- —All endpoints priced at $0.02 per request with no API keys, no rate limitshttps://lowpaymentfee.com
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com