Pay-per-call API platform on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/payments/346` is labeled "Premium API Access" and charges up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — callers simply attach an x402 payment header to each request.
The wider site lists 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. However, no OpenAPI schema, detailed documentation, or example request/response payloads are available — the docs, pricing, and README pages all resolve to a minimal "Connect wallet" prompt with no further content.
Because the endpoint at `/api/v1/payments/346` does not clearly map to any of the named services on the homepage, its exact functionality is uncertain. The x402 challenge confirms it is live, accepts POST requests, returns application/json, and settles via USDC (contract 0x8335…) on Base to address 0x1A2B…. Without documentation or sample responses, agents should treat this as a stub listing until more information becomes available.
Capabilities
Use cases
- —Paying per-call for AI inference (sentiment, summarization, classification, embeddings) without API keys
- —Fetching real-time financial data such as token quotes, exchange rates, and gas estimates
- —Running utility operations like geocoding, validation, and data conversion on demand
- —Exporting analytics data or generating insights reports with micro-payments
Fit
Best for
- —Agents or developers who want keyless, pay-as-you-go API access
- —Crypto-native workflows that can attach x402 USDC payments on Base
- —Low-volume or bursty usage patterns where per-request pricing beats subscriptions
Not for
- —High-volume production workloads needing guaranteed SLAs and detailed documentation
- —Users without a Base-compatible USDC wallet or x402 client
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/346 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and confirms pricing and settlement details, but there is no OpenAPI schema, no documentation beyond a wallet-connect prompt, no example requests or responses, and the specific endpoint path (/api/v1/payments/346) does not clearly correspond to any named service. Effectively a stub.
Warnings
- —No OpenAPI or schema documentation available — docs, pricing, and README pages all show only 'Connect wallet'
- —The endpoint path /api/v1/payments/346 does not match any of the named API paths on the homepage; its exact functionality is unknown
- —No example request or response payloads are available to verify what the endpoint actually returns
- —All non-homepage crawled pages returned minimal content, suggesting documentation is not yet built out
Citations
- —The x402 challenge returns 402 with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/346
- —USDC contract address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/payments/346
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com