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/74` 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 — no API keys, accounts, or subscriptions are required; callers attach an X-PAYMENT header with a signed USDC payment to each request.
The wider 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 listed endpoints share the same $0.02/request pricing. The platform claims no rate limits and instant access.
Important caveat: the specific endpoint probed (`/api/v1/keys/74`) does not clearly map to any of the named API categories on the landing page. Its description is simply "Premium API Access," and no documentation, OpenAPI schema, or example request/response payloads are available. The /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content. Without documentation it is impossible to confirm what this endpoint actually returns or what input it expects beyond an HTTP POST with a JSON content type.
Capabilities
Use cases
- —Programmatic access to paid API endpoints without creating accounts or managing API keys
- —Agent-driven workflows that need on-demand API calls settled in USDC on Base
- —Exploring x402 protocol integration for pay-per-request microservices
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents that need frictionless, keyless API access via crypto micropayments
- —Use cases where per-call pricing at $0.02 is preferable to subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk/subscription pricing
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/74 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live (returns a valid x402 402 challenge), but there is no OpenAPI schema, no documentation, no example requests or responses, and the /api, /pricing, and /README pages are empty beyond a wallet-connect prompt. The endpoint name 'Premium API Access' is generic and does not describe what data or functionality it provides. Effectively a stub listing.
Warnings
- —No documentation available — /api, /pricing, and /README pages returned only 'Connect wallet' with no content
- —The endpoint path /api/v1/keys/74 does not match any of the named endpoints on the landing page; its actual functionality is unknown
- —No OpenAPI or output schema beyond basic HTTP method info
- —No example request or response payloads available to verify behavior
Citations
- —The platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —Pricing is $0.02 per request with no API keys, no rate limits, and instant access on the Base networkhttps://lowpaymentfee.com
- —The x402 challenge for /api/v1/keys/74 specifies maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/keys/74