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. All endpoints are paid per-request using USDC on the Base network at a flat rate of $0.02 per call, with no API keys, no rate limits, and no commitments required.
The specific endpoint at `/api/v1/accounts/121` 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. Payment is made via the x402 exact scheme, settling to the provider's wallet. The endpoint accepts HTTP POST 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 beyond the landing page were largely empty (showing only "Connect wallet"), so detailed request/response schemas for individual endpoints are not available.
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 queries or exporting data with zero upfront commitment
- —Geocoding, validation, or conversion utilities paid per request via USDC on Base
Fit
Best for
- —AI agents and bots that can settle payments via x402 on Base
- —Developers wanting zero-friction API access without signup or API keys
- —Low-volume or bursty workloads where per-request pricing at $0.02 is economical
Not for
- —High-volume production workloads where per-request crypto payment overhead is impractical
- —Users who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/121 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and pricing is clear ($0.02 USDC on Base). However, documentation pages are effectively empty, there is no OpenAPI spec, no request/response schema, and no examples for any endpoint. The specific purpose of /api/v1/accounts/121 ('Premium API Access') is vague and undocumented.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all returned only 'Connect wallet' with no actual content.
- —No OpenAPI or schema available — request and response formats for this endpoint are unknown.
- —The purpose of /api/v1/accounts/121 ('Premium API Access') is not explained anywhere; it may be a generic or placeholder endpoint.
- —The broad catalog of endpoints (AI, finance, analytics, utils) is advertised but none have documented schemas or examples.
Citations
- —Flat pricing of $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/accounts/121
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages returned only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs