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 pay-per-request endpoints across four categories: Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure. Each call costs $0.02 in USDC on the Base network, settled on-chain with no API keys, no rate limits, and no subscriptions required.
The specific endpoint at `/api/v1/payments/194` is listed as "Premium API Access." The x402 challenge confirms it is live, accepting POST requests and requiring up to 20,000 base units of USDC (0x8335…) on Base, which equals $0.02 (USDC uses 6 decimals). Payment is made via the x402 exact scheme to the payTo address. The endpoint returns application/json.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 per request price point. However, documentation beyond the landing page is extremely sparse (docs, pricing, and API pages all render only a "Connect wallet" prompt), so the actual request/response schemas for individual endpoints are unknown.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto token quotes, gas estimates, or exchange rates with per-call payment
- —Running geocoding or data validation utilities paid per request via USDC on Base
Fit
Best for
- —AI agents that can settle x402 payments in USDC on Base
- —Developers wanting zero-commitment, no-signup API access
- —Low-volume or bursty workloads where per-call pricing is economical
Not for
- —High-volume production workloads where $0.02/call adds up quickly
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/194 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing. However, documentation is essentially nonexistent — every page beyond the landing returns only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, and no explanation of what 'Premium API Access' actually returns. The listing is effectively a stub with confirmed liveness.
Warnings
- —No documentation available — docs, pricing, API, and README pages all render only 'Connect wallet'
- —No OpenAPI or request/response schema provided for any endpoint
- —The specific purpose of /api/v1/payments/194 ('Premium API Access') is unclear — it does not map to any of the named endpoints on the landing page
- —Cannot verify what data or functionality any endpoint actually returns
Citations
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/payments/194
- —Available endpoint categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com