Pay-per-request API platform on Base (USDC) via x402 — $0.02/call, no API keys required.
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/inbox/174` is listed as "Premium API Access" and accepts POST requests with payment via USDC (contract 0x8335…2913 on Base). The maximum amount required per call is 20,000 base units of USDC (6 decimals), which equals $0.02 USD.
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 uniformly priced at $0.02 per request. The platform emphasizes no API keys, no rate limits, no minimums, and instant access — payment is handled entirely through the x402 payment header.
This specific endpoint (`/api/v1/inbox/174`) lacks detailed documentation about what it returns or what input it expects beyond being a POST endpoint returning `application/json`. The "Premium API Access" label is generic and does not clarify the endpoint's function. Without further documentation or example responses, the exact capability of this particular endpoint remains unclear.
Capabilities
Use cases
- —Accessing pay-per-request API services without needing API key registration
- —Making micropayment-gated API calls settled in USDC on Base
- —Agent-driven workflows that need on-demand API access with crypto payment
Fit
Best for
- —Developers wanting zero-signup API access via crypto micropayments
- —AI agents that can settle x402 payments autonomously
- —Users who prefer pay-as-you-go pricing without subscriptions
Not for
- —Users who need detailed API documentation and schemas before integrating
- —High-volume use cases where per-request pricing may add up compared to flat-rate plans
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/inbox/174 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (returns 402 with a valid x402 challenge), and pricing is clear ($0.02 USDC on Base). However, there is no documentation on what this specific endpoint does, no input/output schema, no example requests or responses, and the crawled pages beyond the homepage returned only 'Connect wallet' with no useful content. The 'Premium API Access' label is entirely generic.
Warnings
- —No documentation available for /api/v1/inbox/174 — the endpoint's actual function is unknown
- —No input or output schema provided beyond 'application/json' mime type
- —The label 'Premium API Access' is generic and does not describe the endpoint's capability
- —Other crawled pages (/api, /pricing, /README) returned no useful content
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/inbox/174
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/inbox/174
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com