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/35` 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 — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
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 the same $0.02/request price point.
This particular endpoint (`/api/v1/charges/35`) is labeled "Premium API Access" but the crawled material does not clarify what specific data or functionality it returns beyond the generic title. The docs, pricing, and README pages all rendered only a "Connect wallet" prompt with no additional documentation. Without further documentation or example responses, the actual payload returned by this endpoint remains unknown.
Capabilities
Use cases
- —Programmatic access to a pay-per-call API without managing API keys or subscriptions
- —Agent-driven workflows that need on-demand API access settled in USDC on Base
- —Testing x402 protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers exploring x402 payment protocol integrations
- —AI agents that need keyless, pay-as-you-go API access
- —Users who want to avoid subscription commitments for occasional API calls
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/35 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI schema, no example request/response, and the actual functionality behind "Premium API Access" is completely undocumented. The docs, pricing, and README pages are all empty beyond a wallet-connect prompt.
Warnings
- —The actual data or functionality returned by /api/v1/charges/35 is undocumented — 'Premium API Access' is a generic label with no specification.
- —All documentation pages (docs, pricing, README, api) render only a 'Connect wallet' prompt with no usable content.
- —No OpenAPI spec, no example responses, and no input schema are available.
- —The endpoint's purpose cannot be verified without making a paid request.
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/35
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access.https://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base network.https://lowpaymentfee.com/api/v1/charges/35