Pay-per-request API platform on Base network via x402 — $0.02/call in USDC.
What it does
lowpaymentfee.com is an x402-enabled API marketplace that offers a variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no commitments required. The x402 protocol handles payment inline: callers attach an X-PAYMENT header with a signed USDC payment, and the server fulfills the request upon verification.
The specific endpoint at `/api/v1/products/67` is listed as "Premium API Access" and accepts POST requests. Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The site lists 16 endpoints organized into 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 (geocoding, validation, conversion, generation). Documentation pages exist but appear gated behind a wallet connection, so detailed request/response schemas are not publicly available. The exact functionality behind the `/api/v1/products/67` path is unclear — it may be a generic product endpoint or an alias for one of the listed services.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification, embeddings) without managing API keys
- —Fetching real-time crypto gas estimates or token quotes with per-call USDC micropayments
- —Geocoding or data validation as a utility service paid per request on Base
Fit
Best for
- —AI agents with Base USDC wallets needing frictionless API access
- —Developers who want pay-as-you-go pricing without subscriptions or rate limits
- —Web3-native applications that prefer on-chain payment settlement
Not for
- —High-volume batch processing where per-call pricing adds up quickly
- —Users without a Base network USDC wallet or x402-compatible client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/67 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-signed-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no documented request/response format for this specific endpoint, and docs pages are gated behind wallet connection. The purpose of /api/v1/products/67 specifically is ambiguous.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all appear gated behind wallet connection and return no useful content.
- —The exact purpose and expected request/response schema of /api/v1/products/67 is unclear — it does not match any of the 16 listed endpoint paths on the homepage.
- —No OpenAPI spec or detailed API documentation is publicly available.
Citations
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The site offers 16 endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base with 300s timeouthttps://lowpaymentfee.com/api/v1/products/67