Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no upfront commitments. The specific endpoint at `/api/v1/transactions/278` is listed as "Premium API Access" and returns `application/json` via POST.
The platform advertises four main categories of APIs: (1) Data & Analytics — metrics, reports, data export, and insights; (2) AI & Machine Learning — sentiment analysis, text summarization, classification, and embeddings; (3) Finance & Web3 — price feeds, exchange rates, token quotes, and gas estimates; (4) Infrastructure — geocoding, validation, conversion, and generation utilities. All endpoints follow the x402 payment protocol, where callers attach an `X-PAYMENT` header containing a signed USDC payment to unlock the response.
Note that the specific endpoint probed (`/api/v1/transactions/278`) does not appear in the site's published API catalog, and its actual functionality beyond the generic "Premium API Access" label is unclear. Documentation pages (docs, pricing, README) all returned only a "Connect wallet" prompt with no substantive content. Without request/response schemas or detailed docs, the exact behavior of this endpoint cannot be confirmed.
Capabilities
Use cases
- —Accessing premium API data without managing API keys or subscriptions
- —Making one-off paid API calls from autonomous agents using x402 USDC payments
- —Integrating pay-per-use analytics, AI inference, or financial data into applications
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost ($0.02) per-request API calls without signup
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume use cases where per-request pricing may add up compared to subscription plans
- —Users without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/278 \
-H "X-PAYMENT: <x402-signed-payment-header>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, this specific endpoint path (/api/v1/transactions/278) is not listed in the site's catalog, documentation pages are empty stubs, and there is no OpenAPI schema, request/response examples, or explanation of what 'Premium API Access' actually returns.
Warnings
- —The endpoint /api/v1/transactions/278 does not appear in the site's published API catalog — its actual functionality is unknown.
- —All documentation pages (/docs, /pricing, /README, /api) returned only 'Connect wallet' with no substantive content.
- —No OpenAPI spec, request schema, or response schema is available for this endpoint.
- —The purpose and data returned by 'Premium API Access' cannot be verified from available materials.
Citations
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The platform offers APIs across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com
- —The x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base network, equaling $0.02.https://lowpaymentfee.com/api/v1/transactions/278
- —Documentation pages returned only 'Connect wallet' with no substantive content.https://lowpaymentfee.com/docs