Pay-per-request API platform on Base network via x402 — $0.02/call in USDC.
What it does
lowpaymentfee.com is an x402-enabled API marketplace that offers a broad set of endpoints spanning 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 x402 protocol handles payment inline: callers attach a signed USDC payment in the X-PAYMENT header and receive the response immediately.
The specific endpoint at `/api/v1/products/38` is listed as "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requesting up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) on Base (asset contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913). The payment is settled 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 further content. There is no OpenAPI schema, no request/response examples, and no description of what the `/api/v1/products/38` endpoint actually returns beyond its title. The landing page lists sibling endpoints across categories (analytics, AI, finance, utilities) but provides no technical detail about input parameters or output formats for any of them.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Exploring x402 protocol integration for automated crypto-settled API calls
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that can sign USDC transactions on Base
- —Low-volume, on-demand API consumers who prefer no subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who need bulk pricing or rate-limit guarantees
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/38 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no documentation, 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 docs pages are empty stubs.
Warnings
- —No documentation available — docs, pricing, API, and README pages all show only 'Connect wallet' with no content
- —No OpenAPI or input/output schema provided for this endpoint
- —The purpose and response format of /api/v1/products/38 ('Premium API Access') is completely undocumented
- —Cannot verify what data or service this endpoint actually provides
Citations
- —Endpoint returns a valid x402 402 challenge requesting 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/products/38
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/38
- —The platform offers endpoints across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com