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 utility services. 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 a payment header to each HTTP request and receive the response immediately upon settlement.
The specific endpoint at `/api/v1/transactions/347` is listed as "Premium API Access" and returns an x402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
The broader platform advertises endpoints in 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 to require wallet connection to view, so detailed request/response schemas are not available from the crawl.
Capabilities
Use cases
- —Querying real-time crypto price feeds and gas estimates without an API key
- —Running sentiment analysis or text summarization on demand with per-call USDC payment
- —Exporting data or generating analytics reports via pay-as-you-go endpoints
- —Geocoding addresses or validating data through utility endpoints
Fit
Best for
- —Developers wanting zero-commitment, pay-per-call API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing lightweight access to multiple API categories without subscription overhead
Not for
- —High-volume production workloads where per-request pricing at $0.02 adds up quickly
- —Users without USDC on the Base network or an x402-compatible client
- —Applications requiring detailed SLAs, guaranteed uptime, or dedicated support
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/347 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base). However, documentation pages all require wallet connection and yield no content, so there are no request/response schemas, no example payloads, and no detailed descriptions of what each endpoint actually returns. The specific /transactions/347 endpoint's purpose beyond 'Premium API Access' is unclear.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all render only a 'Connect wallet' prompt — no usable docs were crawled.
- —No OpenAPI spec or request/response schema is available; endpoint behavior must be inferred.
- —The purpose of /api/v1/transactions/347 specifically (vs. other endpoints) is not documented.
- —The breadth of advertised capabilities (AI, finance, geocoding, etc.) could not be independently verified.
Citations
- —The endpoint returns an x402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/347
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform offers endpoints in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/347