Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request 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 priced at $0.02 per request, payable in USDC on the Base network via the x402 protocol.
The specific endpoint `/api/v1/keys/17` is listed as "Premium API Access" and carries a maxAmountRequired of 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals). Payment is made to a designated Ethereum address on Base, with no API keys, rate limits, or upfront commitments required. The x402 challenge was confirmed live, returning a proper 402 response with version 1 of the protocol.
Documentation is minimal — the landing page lists available endpoints and pricing, but there is no OpenAPI spec, no request/response schema documentation, and no usage examples. The `/api`, `/pricing`, and `/README` pages all returned only a "Connect wallet" prompt with no additional content. Because of this, the actual behavior and response format of the Premium API Access endpoint (and the other listed endpoints) cannot be verified from the crawl alone.
Capabilities
Use cases
- —Accessing AI inference (sentiment, summarization, classification, embeddings) on a per-call basis without subscriptions
- —Fetching real-time crypto token quotes and gas estimates for DeFi applications
- —Running geocoding or data validation as a lightweight utility service
- —Exporting analytics data or generating insights reports on demand
Fit
Best for
- —Agents or apps that need occasional, low-cost API calls without managing API keys
- —Developers prototyping with AI/ML endpoints who want instant access
- —Web3-native applications already operating on the Base network
Not for
- —High-volume production workloads where per-request pricing adds up quickly
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
- —Applications requiring non-USDC or non-Base payment methods
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/17 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no usage examples, and the docs pages are empty beyond a wallet-connect prompt. The actual functionality behind this specific endpoint is undocumented.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The /api, /pricing, and /README pages return only a 'Connect wallet' prompt with no useful content
- —The specific behavior and response format of /api/v1/keys/17 ('Premium API Access') is unclear — it may be a meta-endpoint for key generation rather than a data endpoint
- —No information on uptime, SLAs, or rate limits beyond the marketing claim of 'no rate limits'
Citations
- —All endpoints priced at $0.02 per request with no minimums or commitmentshttps://lowpaymentfee.com
- —Payment in USDC on Base network, maxAmountRequired of 20000 base units (= $0.02)https://lowpaymentfee.com/api/v1/keys/17
- —Categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access advertisedhttps://lowpaymentfee.com
- —x402 challenge confirmed live with 402 status and version 1https://lowpaymentfee.com/api/v1/keys/17