Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint `/api/v1/keys/8` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). No API keys, rate limits, or subscriptions are required — each request is paid individually via the x402 protocol.
The wider platform advertises four endpoint 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 utilities (geocoding, validation, conversion, generation). All endpoints are listed at the same $0.02 per request price point.
The specific functionality behind `/api/v1/keys/8` ("Premium API Access") is not documented in detail. The crawled pages beyond the landing page returned only wallet-connect prompts with no additional documentation, OpenAPI spec, or usage examples. The endpoint is confirmed live via a valid 402 challenge, but what data or service it returns upon successful payment is unclear.
Capabilities
Use cases
- —Agents needing on-demand API access without managing API keys or subscriptions
- —Paying per-call for AI inference tasks like sentiment analysis or text summarization
- —Fetching real-time financial data (prices, exchange rates, gas estimates) with micropayments
- —Geocoding or data validation without rate limits
Fit
Best for
- —AI agents that need frictionless, keyless API access via x402
- —Developers who want pay-as-you-go pricing with no commitments
- —Use cases requiring low-cost micropayment-settled API calls on Base
Not for
- —High-volume production workloads where per-call pricing becomes expensive compared to subscription APIs
- —Users who need detailed API documentation, schemas, or SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/8 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, but there is no OpenAPI spec, no documentation beyond a landing page listing, and no examples or response schemas. The actual functionality of /api/v1/keys/8 ('Premium API Access') is entirely opaque — it could be an API key provisioning endpoint or something else. Effectively a stub listing.
Warnings
- —No OpenAPI spec or schema available for any endpoint
- —The specific purpose of /api/v1/keys/8 ('Premium API Access') is undocumented — unclear what it returns
- —All documentation pages beyond the landing page returned only 'Connect wallet' with no content
- —No response examples or error documentation available
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/keys/8
- —All endpoints are priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/keys/8