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 set of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are paid per-request at $0.02 each using USDC on the Base network, with no API keys, no rate limits, and no minimum commitments required. The specific endpoint at `/api/v1/transactions/122` is labeled "Premium API Access" and advertises a maximum cost of 20,000 base units of USDC (i.e., $0.02) per call.
The platform's landing page lists 16 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 (geocoding, validation, conversion, generation). All are priced identically at $0.02 per request.
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI schema, no request/response examples, and no detailed documentation for any endpoint. The x402 challenge on the probed endpoint is live and well-formed, confirming the endpoint accepts POST requests and settles payments in USDC on Base. However, without documentation or example payloads, it is unclear what request body this specific endpoint expects or what response it returns.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data like token quotes, exchange rates, and gas estimates on a per-call basis
- —Running data analytics queries and exporting data with per-request USDC micropayments
- —Using utility services like geocoding, validation, and conversion without subscriptions
Fit
Best for
- —Developers who want pay-per-use API access without signup or API keys
- —Agents and bots that can settle x402 payments in USDC on Base
- —Projects needing low-cost, commitment-free access to a variety of utility and data endpoints
Not for
- —Users who need detailed API documentation and well-defined schemas before integrating
- —High-volume production workloads that benefit from bulk pricing or rate-limit guarantees
- —Users without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/122 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and well-formed, confirming the endpoint works and costs $0.02 USDC on Base. However, there is no OpenAPI schema, no request/response examples, and all documentation pages are empty beyond a wallet-connect prompt. The purpose of this specific endpoint (/api/v1/transactions/122) is unclear, and the broader platform's endpoints lack any documented input/output contracts.
Warnings
- —No API documentation available — /docs, /api, /pricing, and /README pages all show only 'Connect wallet' with no content
- —No OpenAPI or JSON schema provided for any endpoint
- —The specific endpoint /api/v1/transactions/122 is not listed among the 16 endpoints on the landing page — its purpose is unknown
- —No request or response examples available anywhere in crawled content
- —Cannot verify what data or functionality any endpoint actually provides
Citations
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform lists 16 endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —The x402 challenge on /api/v1/transactions/122 returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/122