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 utility services. All endpoints are pay-per-request at $0.02 each, settled in USDC on the Base network. No API keys, accounts, or rate limits are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/370` is listed as "Premium API Access" and advertises a max cost of 20,000 base units of USDC (0.02 USDC, i.e., $0.02) per call. The x402 challenge confirms the endpoint is live, accepts the `exact` payment scheme on Base, and pays out to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`. The asset contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` is Base-native USDC.
The broader platform advertises categories including metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation endpoints — all at the same $0.02 price point. However, documentation pages (docs, pricing, README) returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints remain unverified.
Capabilities
Use cases
- —Accessing analytics metrics and reports without needing an API key or subscription
- —Running AI inference tasks (sentiment analysis, summarization, classification, embeddings) on a per-call basis
- —Fetching real-time crypto token quotes, gas estimates, and exchange rates
- —Geocoding addresses or validating data via utility endpoints
Fit
Best for
- —Developers who want instant, keyless API access with crypto micropayments
- —Agents and bots that need pay-per-call endpoints without account setup
- —Projects already operating on the Base network with USDC
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/370 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and confirms pricing and payment details, but the endpoint's actual functionality behind "Premium API Access" is completely undocumented. All docs/pricing/README pages returned only a wallet-connect prompt with no content. No request or response schemas are available, making integration speculative.
Warnings
- —The specific purpose and response format of /api/v1/transactions/370 ('Premium API Access') is unknown — no documentation or schema is available.
- —All documentation pages (docs, pricing, README) returned only 'Connect wallet' with no substantive content.
- —The broad catalog of advertised endpoints (AI, analytics, finance, utilities) could not be verified for actual functionality.
- —No OpenAPI spec, input schema, or output schema is provided beyond the minimal x402 outputSchema stub.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0.02 USDC) on Base network for /api/v1/transactions/370.https://lowpaymentfee.com/api/v1/transactions/370
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.https://lowpaymentfee.com/api/v1/transactions/370
- —Platform advertises categories: Data & Analytics, AI & Machine Learning, Finance & Web3, Infrastructure.https://lowpaymentfee.com