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/charges/189` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an x402 payment header to each request.
The broader platform offers endpoints across four categories: 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 $0.02 per request.
However, the specific endpoint `/api/v1/charges/189` does not clearly map to any of the named API categories on the site. Its description is simply "Premium API Access" with no further documentation about what data or functionality it returns. The docs, pricing, and README pages all render only a "Connect wallet" prompt with no substantive content. Without an OpenAPI schema, example responses, or detailed documentation, it is unclear what this particular endpoint actually does when a valid payment is submitted.
Capabilities
Use cases
- —Programmatic access to pay-per-request APIs without subscription or API key management
- —Agent-driven API consumption where each call is settled on-chain via USDC on Base
- —Exploring x402 protocol integration for micropayment-gated endpoints
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need keyless, on-demand API access settled in USDC
- —Low-volume or sporadic API consumers who prefer per-call pricing
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —High-volume consumers where $0.02/request adds up significantly compared to subscription plans
- —Anyone requiring non-crypto payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/189 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no OpenAPI schema, no documentation beyond a landing page, no example requests or responses, and the specific endpoint's purpose ('Premium API Access') is entirely opaque. The docs/pricing/README pages are empty beyond a wallet connect prompt.
Warnings
- —The specific endpoint /api/v1/charges/189 has no documentation explaining what it returns upon successful payment.
- —All documentation pages (docs, pricing, README, api) render only 'Connect wallet' with no substantive content.
- —No OpenAPI or schema available — request/response formats are unknown.
- —The endpoint name 'Premium API Access' does not correspond to any of the named APIs on the landing page.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base network.https://lowpaymentfee.com/api/v1/charges/189
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access.https://lowpaymentfee.com
- —The USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base.https://lowpaymentfee.com/api/v1/charges/189
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure.https://lowpaymentfee.com