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 variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are pay-per-request at $0.02 each, settled in USDC on the Base network. No API keys, accounts, or rate limits are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transfers/66` is listed as "Premium API Access" and carries a max amount of 20,000 base units of USDC (0.02 USDC, i.e., $0.02 per call). 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). However, the crawled documentation pages (docs, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints remain unverified.
The endpoint is confirmed live — it returns a proper 402 challenge with x402 version 1, accepting the "exact" payment scheme on Base with USDC (contract 0x8335…2913). The payment recipient is 0x1A2B…85F3 with a 300-second timeout. Without detailed documentation or example responses, the precise functionality behind the "Premium API Access" label for this particular transfer endpoint is unclear.
Capabilities
Use cases
- —Accessing AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data and crypto gas estimates on a per-call basis
- —Running geocoding or data validation utilities with instant crypto-settled payments
- —Exporting analytics data or generating reports without subscription commitments
Fit
Best for
- —Developers who want zero-friction, keyless API access paid in USDC
- —Agents and bots that can attach x402 payment headers automatically
- —Users who need occasional API calls without committing to a subscription
Not for
- —High-volume production workloads where per-call pricing may add up
- —Users without a Base-network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/66 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid 402 challenge and clear pricing ($0.02 USDC per call on Base). However, documentation pages are empty (only 'Connect wallet'), there is no OpenAPI schema, no example requests or responses, and the specific purpose of '/api/v1/transfers/66' is unclear beyond the generic 'Premium API Access' label.
Warnings
- —Documentation pages (/docs, /pricing, /README) returned no useful content — only 'Connect wallet' prompts.
- —The specific functionality of /api/v1/transfers/66 ('Premium API Access') is not documented; its purpose is unclear.
- —No OpenAPI spec or response schema is available for any endpoint.
- —The broad range of advertised capabilities (AI, finance, geocoding, etc.) cannot be verified from crawl data alone.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The 402 challenge specifies maxAmountRequired of 20000 base units of USDC (0.02 USD) on Base network with exact schemehttps://lowpaymentfee.com/api/v1/transfers/66
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transfers/66
- —Platform advertises Data & Analytics, AI & ML, Finance & Web3, and Infrastructure API categorieshttps://lowpaymentfee.com