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 priced at $0.02 per request, payable in USDC on the Base network with no API keys, no rate limits, and no commitments required. The x402 payment protocol allows agents and users to pay per call by attaching a cryptographic payment header to each HTTP request.
The specific endpoint at `/api/v1/transactions/312` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts POST requests and returns `application/json`. Payment is sent to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout.
Documentation is extremely sparse — the docs, pricing, API, and README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of what the `/api/v1/transactions/312` endpoint actually returns. The landing page lists many other endpoints but does not describe this specific one beyond its title. Without further documentation it is unclear what data or functionality this particular endpoint provides.
Capabilities
Use cases
- —Programmatic access to premium API data without requiring API key registration
- —Agent-driven workflows that need to pay per call using USDC on Base
- —Accessing transaction or financial data via a single HTTP POST with embedded payment
Fit
Best for
- —Developers or agents wanting zero-signup, pay-per-use API access
- —x402-compatible clients on the Base network
- —Scenarios requiring no rate limits and instant access
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume use cases where per-request pricing at $0.02 may be costly
- —Anyone without USDC on Base or an x402-compatible payment client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/312 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, documentation is essentially nonexistent — all doc/pricing/API pages show only 'Connect wallet'. There is no OpenAPI schema, no request/response examples, and no description of what this specific endpoint actually does beyond the generic title 'Premium API Access'. The listing is effectively a stub.
Warnings
- —No documentation available — docs, pricing, API, and README pages all render only 'Connect wallet'
- —No OpenAPI or schema describing request parameters or response format for /api/v1/transactions/312
- —The purpose and output of this specific endpoint are unknown; 'Premium API Access' is not descriptive
- —The broader platform lists many endpoints but none have documented schemas or examples
Citations
- —All endpoints priced at $0.02/request with no API keys, no rate limits, 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/transactions/312
- —Payment address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with 300-second timeouthttps://lowpaymentfee.com/api/v1/transactions/312
- —Docs, pricing, API, and README pages render only 'Connect wallet' with no substantive contenthttps://lowpaymentfee.com/docs