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 set of endpoints across 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 specific endpoint at `/api/v1/transactions/31` is listed as "Premium API Access" and returns an x402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02, since USDC uses 6 decimals) on Base.
The platform advertises four categories of APIs: 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 utilities (geocoding, validation, conversion, generation). All are priced uniformly at $0.02 per call.
Documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no detailed documentation available from the crawl. The actual functionality behind the `/api/v1/transactions/31` endpoint is unclear; the description "Premium API Access" is generic and does not specify what data or service is returned.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data like token quotes, exchange rates, and gas estimates
- —Running data analytics queries and exporting reports on a per-request payment basis
- —Using utility services like geocoding, validation, and data conversion with micropayments
Fit
Best for
- —Developers who want instant API access without signup or API keys
- —Agents and bots that can settle payments in USDC on Base via x402
- —Low-volume or sporadic API consumers who prefer pay-per-use over subscriptions
Not for
- —High-volume production workloads needing SLAs and guaranteed uptime documentation
- —Users who need detailed API documentation, request/response schemas, or sandbox environments
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/31 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but documentation is essentially nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI schema, no request/response examples, and the purpose of the specific /api/v1/transactions/31 endpoint is unclear beyond the generic label 'Premium API Access'. Pricing is clear ($0.02/request in USDC on Base).
Warnings
- —Documentation pages (docs, API, pricing, README) all render only 'Connect wallet' with no usable content
- —No OpenAPI or schema definition available for any endpoint
- —The specific endpoint /api/v1/transactions/31 has a generic 'Premium API Access' description — its actual functionality is unknown
- —No request or response examples are available anywhere in the crawl
Citations
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge for /api/v1/transactions/31 requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/31
- —Platform offers APIs across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com