Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. Every endpoint is priced at $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no upfront commitments. The x402 payment challenge is live and returns a standard 402 response with an exact-scheme payment requirement.
The specific endpoint at `/api/v1/transfers/120` is listed as "Premium API Access" and accepts POST requests. Based on the x402 challenge, the maximum amount required is 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is settled on-chain to the specified payTo address. 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 spec, no request/response schema documentation, and no usage examples available from the crawl. The actual functionality behind the `/api/v1/transfers/120` endpoint is unclear; the name "Premium API Access" and the path segment "transfers" do not map obviously to any of the advertised API categories.
Capabilities
Use cases
- —Accessing data analytics or AI inference endpoints without managing API keys or subscriptions
- —Making one-off API calls with instant USDC micropayments on Base
- —Integrating pay-per-use financial data feeds into agent workflows
- —Using geocoding or text processing utilities with no rate limits
Fit
Best for
- —Developers who want zero-friction, keyless API access via crypto micropayments
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost per-call pricing without monthly commitments
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Teams that require fiat-only payment methods with no crypto wallet
- —High-volume consumers who need bulk pricing or SLA guarantees
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/120 \
-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 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the specific purpose of the /transfers/120 endpoint is ambiguous. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — all /docs, /pricing, /api, /README pages return only 'Connect wallet'
- —The purpose of /api/v1/transfers/120 ('Premium API Access') is unclear and does not match any of the advertised API categories
- —No request body schema or response schema is documented anywhere
- —No examples of successful responses are available
Citations
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transfers/120
- —API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs