Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/transfers/83` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an X-PAYMENT header with a valid x402 payment proof to each request.
The broader platform offers 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 listed at the same $0.02/request price point and settle in USDC on Base.
Note that the specific endpoint probed (`/api/v1/transfers/83`) does not clearly map to any of the documented API categories on the landing page, and the description "Premium API Access" is generic. There is no OpenAPI schema, no detailed documentation, and no example request/response payloads available from the crawled pages. The docs, pricing, and API pages all rendered only a "Connect wallet" prompt with no additional content.
Capabilities
Use cases
- —Accessing premium API endpoints without traditional API key registration
- —Making one-off paid API calls settled in USDC on Base
- —Agent-driven workflows that need instant, keyless API access with crypto payment
Fit
Best for
- —Developers who want to pay per request with no subscription or signup
- —AI agents that can attach x402 payment headers automatically
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who prefer flat-rate or subscription pricing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/83 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"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 documentation beyond a landing page, no example requests or responses, and the specific endpoint '/api/v1/transfers/83' doesn't match any documented API category. The docs/pricing/API pages are all empty beyond a wallet-connect prompt.
Warnings
- —The endpoint path '/api/v1/transfers/83' does not correspond to any documented API on the landing page — its actual functionality is unknown.
- —No OpenAPI schema or detailed documentation is available; docs, pricing, and API pages render only 'Connect wallet'.
- —No example request or response payloads are available to verify what this endpoint actually returns.
- —The description 'Premium API Access' is generic and does not clarify the endpoint's purpose.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Basehttps://lowpaymentfee.com/api/v1/transfers/83
- —The platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —The platform advertises no API keys, no rate limits, instant access, and Base network settlementhttps://lowpaymentfee.com
- —USDC asset contract on Base: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transfers/83