Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint at `/api/v1/payments/65` is labeled "Premium API Access" and charges up to 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals) per call. No API keys, rate limits, or subscriptions are required — each request is individually settled on-chain.
The broader platform advertises multiple API categories including 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/request price point. However, the specific functionality behind the `/api/v1/payments/65` endpoint is not documented beyond its "Premium API Access" label, and the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further technical documentation.
The endpoint is live and returns a valid x402 challenge (HTTP 402) with payment details specifying the USDC contract on Base (`0x8335...2913`). The payment recipient is `0x1A2B...85F3`. The endpoint accepts POST requests and returns `application/json`. Due to the lack of detailed documentation about request/response schemas and the unclear nature of what "Premium API Access" actually returns, users should treat this as an exploratory endpoint.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments
- —Integrating pay-as-you-go API calls without managing API keys or subscriptions
- —Agent-driven API consumption where each call is individually settled on-chain
Fit
Best for
- —Developers wanting zero-commitment, per-call API access
- —AI agents that can autonomously pay for API calls via x402
- —Users already holding USDC on the Base network
Not for
- —Users needing detailed API documentation or guaranteed SLAs before purchasing
- —High-volume use cases where per-request on-chain settlement adds overhead
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/65 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation on what the endpoint actually does, no request/response schema, and the docs/pricing/API pages are empty beyond a wallet connect prompt. The listing is effectively a stub with confirmed liveness.
Warnings
- —No documentation available — docs, pricing, and API pages all show only 'Connect wallet' with no content
- —The specific functionality of /api/v1/payments/65 ('Premium API Access') is completely undocumented
- —No request body schema or response schema is provided
- —The platform lists many API categories (AI, finance, analytics, etc.) but none have visible documentation
Citations
- —Endpoint returns HTTP 402 with x402 challenge specifying USDC on Base network at maxAmountRequired of 20000 base unitshttps://lowpaymentfee.com/api/v1/payments/65
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/payments/65
- —Multiple API categories listed including Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com