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 priced at $0.02 per request, payable 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 a payment header to each request and receive the response immediately.
The specific endpoint `/api/v1/customers/18` is listed as "Premium API Access" and returns `application/json`. Based on the x402 challenge, it accepts POST requests and charges a maximum of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) per call, settled on the Base L2 network to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation. Documentation pages exist but appear to require wallet connection to view, so detailed schemas and example payloads for each endpoint are not publicly available. The purpose of the `/api/v1/customers/18` endpoint specifically is unclear from the available material — it may be a customer data lookup or a demo endpoint.
Capabilities
Use cases
- —Accessing premium API data without managing API keys or subscriptions
- —Agent-driven workflows that need inline micropayment-settled API calls
- —Programmatic access to customer or resource data with per-request USDC payment
- —Testing x402 protocol integrations on Base network
Fit
Best for
- —Developers building x402-compatible agents that pay per call
- —Users who want no-commitment, no-signup API access
- —Crypto-native applications settling microtransactions on Base
Not for
- —Users who need free or ad-supported API access
- —High-volume batch processing where per-request fees add up quickly
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/customers/18 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation beyond the landing page, no example request/response bodies, and the specific purpose of /api/v1/customers/18 is ambiguous. Docs pages all just show 'Connect wallet' with no content.
Warnings
- —The specific purpose of /api/v1/customers/18 ('Premium API Access') is not documented — it is unclear what data it returns.
- —All documentation, pricing, and README pages require wallet connection and contain no visible content.
- —No OpenAPI spec or request/response schemas are available.
- —The platform lists many endpoints but none have publicly visible documentation.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0.02 USD) on Base networkhttps://lowpaymentfee.com/api/v1/customers/18
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/customers/18
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com