Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad set 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. The x402 protocol means there are no API keys, no sign-ups, and no rate limits — callers simply attach an X-PAYMENT header with a valid payment proof to each request.
The specific endpoint at `/api/v1/payments/1` is listed as "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform advertises 16+ endpoints across 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 a wallet connection and contain no visible content. No OpenAPI spec or detailed request/response schemas were found, so the exact input parameters and response formats for each endpoint remain unknown.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification, embeddings) without managing API keys
- —Fetching real-time crypto token quotes, gas estimates, or exchange rates with per-call payment
- —Running data analytics or generating reports via simple HTTP POST with USDC micropayments
- —Geocoding, data validation, or format conversion as utility microservices
Fit
Best for
- —AI agents and bots that can settle payments on Base via x402
- —Developers who want instant API access without sign-up or subscription
- —Low-volume or bursty workloads where $0.02/call flat pricing is economical
Not for
- —High-volume production workloads where per-call costs would accumulate significantly
- —Users who cannot transact in USDC on the Base network
- —Applications requiring detailed SLAs, guaranteed uptime, or support contracts
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/1 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and confirms pricing and network details. However, there is no OpenAPI spec, no documentation content (all doc pages just show 'Connect wallet'), no request/response schemas, and no examples. The purpose of the specific /api/v1/payments/1 endpoint is unclear beyond the generic 'Premium API Access' label.
Warnings
- —No OpenAPI or schema documentation available — request/response formats are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no visible content
- —The specific endpoint /api/v1/payments/1 is not listed among the 16 advertised endpoints on the homepage; its exact function is unclear
- —No rate limit or uptime guarantees documented
Citations
- —The platform offers 16+ endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02 per request with no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —The x402 challenge at /api/v1/payments/1 requires up to 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, paid to 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/payments/1