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 `/api/v1/transfers/2` is listed as "Premium API Access" and accepts POST requests. The platform advertises a flat $0.02 per request across all its endpoints, with no API keys, no rate limits, and instant access.
The site offers four broad categories of endpoints: 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 priced at $0.02 per call.
The x402 challenge for this specific endpoint shows a `maxAmountRequired` of 20000 base units of USDC (contract `0x8335...2913` on Base), which equals $0.02 given USDC's 6 decimals. Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`. The endpoint is live and returns a proper 402 challenge. However, documentation is extremely sparse — the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. The actual behavior, request format, and response schema for the `/api/v1/transfers/2` endpoint are unknown.
Capabilities
Use cases
- —Programmatic access to a premium API endpoint with per-call USDC micropayments
- —Agent-driven workflows that need keyless, pay-as-you-go API access on Base
- —Testing x402 protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless API access with crypto micropayments
- —Low-volume, on-demand API consumption without subscriptions
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —High-volume use cases where $0.02/request adds up significantly
- —Users without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/2 \
-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 at $0.02 USDC on Base. However, there is no documentation, no OpenAPI schema, no request/response examples, and the purpose of the specific '/api/v1/transfers/2' endpoint is entirely unclear beyond the generic label 'Premium API Access'. The docs/pricing/README pages are all empty wallet-connect stubs.
Warnings
- —No documentation available — docs, pricing, and README pages all show only 'Connect wallet' with no content
- —The purpose and expected input/output of /api/v1/transfers/2 is unknown; 'Premium API Access' is not descriptive
- —No OpenAPI schema or response schema provided
- —Cannot verify what data or service this endpoint actually returns
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transfers/2
- —Platform advertises $0.02/request flat pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transfers/2
- —The site offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com