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 settled in USDC on the Base network. The specific endpoint at `/api/v1/keys/46` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). Payment is handled via the x402 protocol — callers attach an X-PAYMENT header with a signed payment to the payTo address, and the endpoint returns its response as application/json.
The platform advertises four endpoint 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 per request price point. The platform claims no API keys, no rate limits, no minimums, and instant access.
Important caveat: the specific endpoint `/api/v1/keys/46` does not appear in the publicly listed catalog on the landing page, and its exact functionality is unclear — the description simply says "Premium API Access." There is no OpenAPI schema, no request/response examples, and the docs/pricing/README pages all resolve to a wallet-connect prompt with no additional content. Prospective callers should be aware that the actual behavior behind this endpoint is undocumented.
Capabilities
Use cases
- —Programmatic access to a pay-per-call API without needing API keys or subscriptions
- —Agent-driven workflows that need on-demand endpoint access settled in USDC on Base
- —Testing x402 payment flows against a live endpoint
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously on Base
- —Prototyping x402 integrations with low per-call costs
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where $0.02/request adds up without volume discounts
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/46 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live (returns a valid 402 challenge) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, no documentation beyond a landing page catalog, and the specific endpoint /api/v1/keys/46 is not listed in the public catalog. Its actual functionality is unknown.
Warnings
- —The endpoint /api/v1/keys/46 is not listed in the public catalog — its purpose is undocumented.
- —No OpenAPI spec, no request/response schema, and no example payloads are available.
- —Docs, pricing, and README pages all resolve to a wallet-connect prompt with no content.
- —Claims like 'no rate limits' are unverified and may not hold under load.
Citations
- —Platform lists endpoints at $0.02/request with categories: Data & Analytics, AI & ML, Finance & Web3, Infrastructurehttps://lowpaymentfee.com
- —Pricing is $0.02/request with no API keys, no rate limits, no minimums, instant access, on Base networkhttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/keys/46