Pay-per-call API platform on Base network via x402 — $0.02/request in USDC, no API keys required.
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 pay-per-request using USDC on the Base network, settled via the x402 protocol. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an X-PAYMENT header with each request.
The specific endpoint at `/api/v1/products/91` is listed as "Premium API Access" and accepts POST requests. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per call (USDC uses 6 decimals). The broader platform advertises a uniform $0.02/request price across all its endpoints.
The platform's catalog includes sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data export endpoints. Documentation pages exist but appear to require wallet connection to view, so detailed request/response schemas are not available from the crawl. The endpoint is confirmed live, returning a proper 402 challenge.
Capabilities
Use cases
- —Agents needing on-demand API access without managing API keys or subscriptions
- —Programmatic access to AI inference (sentiment, summarization, classification, embeddings) at low per-call cost
- —Fetching real-time financial data, exchange rates, or gas estimates with micropayments
- —Geocoding, data validation, or format conversion as utility microservices
Fit
Best for
- —AI agents that need keyless, pay-as-you-go API access on Base
- —Developers prototyping with multiple API categories without signup friction
- —Low-volume or bursty workloads where per-request pricing is more economical than subscriptions
Not for
- —High-volume production workloads where bulk pricing would be cheaper
- —Users who need detailed SLAs, uptime guarantees, or enterprise support
- —Callers without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/91 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge and clear pricing ($0.02 USDC on Base). However, documentation pages require wallet connection and returned no useful content. There is no OpenAPI schema, no request/response examples, and the specific purpose of '/api/v1/products/91' beyond 'Premium API Access' is unclear. The platform lists many endpoint categories but details are absent.
Warnings
- —Documentation pages (/docs, /pricing, /api, /README) all returned only 'Connect wallet' with no usable content
- —No OpenAPI or schema available — request and response formats are unknown
- —The specific function of /api/v1/products/91 ('Premium API Access') is not described beyond its title; it does not match any of the named endpoints on the landing page
- —Platform appears to be a generic multi-category API marketplace; actual data sources and model quality are unverified
Citations
- —Uniform pricing of $0.02 per request across all endpoints, no API keys, no rate limitshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (6 decimals = $0.02) on Base networkhttps://lowpaymentfee.com/api/v1/products/91
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/products/91
- —Platform offers endpoints in categories: Data & Analytics, AI & Machine Learning, Finance & Web3, Infrastructurehttps://lowpaymentfee.com