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/transactions/72` 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 the same $0.02/request price point.
However, the specific endpoint being listed here (`/api/v1/transactions/72`) does not clearly map to any of the documented API categories. Its description is simply "Premium API Access" with no further documentation on what data or functionality it returns. The docs, pricing, and API pages all render only a "Connect wallet" prompt with no additional technical detail. Without an OpenAPI schema, request/response examples, or meaningful documentation, the actual behavior of this endpoint remains unclear.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to analytics, AI, finance, or utility endpoints
Fit
Best for
- —Developers wanting keyless, pay-per-use API access settled in USDC
- —AI agents that can attach x402 payment headers autonomously
- —Users on the Base L2 network looking for low-fee API micropayments
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Applications requiring free or subscription-based API access
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/72 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts USDC on Base at $0.02/request. However, there is no OpenAPI schema, no request/response examples, no documentation beyond a wallet-connect prompt, and the specific endpoint path (/api/v1/transactions/72) is not explained anywhere on the site. The listing is essentially a stub.
Warnings
- —No OpenAPI or schema documentation available for this endpoint
- —The endpoint path /api/v1/transactions/72 does not match any documented API category on the site
- —All documentation pages (docs, pricing, API, README) render only 'Connect wallet' with no technical content
- —Actual request body format and response structure are unknown
- —The platform appears to be a generic demo or placeholder — all 16+ endpoints share identical $0.02 pricing with no detailed descriptions
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/72
- —The USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/72
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The site lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com