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 exposes a broad catalog of 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 — no API keys, no rate limits, and no upfront commitments.
The specific endpoint at `/api/v1/messages/135` is described as "Premium API Access" in the x402 challenge. Its maxAmountRequired is 20,000 base units of USDC (6 decimals), which equals $0.02. The endpoint accepts HTTP POST requests and returns application/json. Payment is settled on-chain to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 using the "exact" payment scheme with a 300-second timeout.
Note that while the landing page lists many endpoints, the specific purpose of `/api/v1/messages/135` is not clearly documented beyond the generic "Premium API Access" label. No OpenAPI schema, request/response examples, or detailed documentation were found during crawling — the /api, /pricing, and /README pages all returned only a "Connect wallet" prompt. The platform's actual data sources, model providers, and response formats remain unspecified.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data such as token quotes, gas estimates, and exchange rates on a per-call basis
- —Running utility operations like geocoding, validation, and data conversion with micropayments
- —Integrating pay-as-you-go analytics and data export into agent workflows
Fit
Best for
- —Agents or developers wanting zero-signup, pay-per-call API access
- —Use cases requiring low-cost micropayment-settled API calls on Base
- —Prototyping or low-volume workloads where $0.02/request is economical
Not for
- —High-volume production workloads where per-request crypto settlement overhead matters
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/135 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI schema, no request/response examples, and no documentation beyond the landing page listing. The specific purpose of /api/v1/messages/135 is unclear — it could be a messaging endpoint or a generic placeholder. Most crawled pages returned only 'Connect wallet' with no useful content.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The specific function of /api/v1/messages/135 is undocumented beyond the generic 'Premium API Access' label
- —Crawled /api, /pricing, and /README pages returned no useful content (only 'Connect wallet')
- —No request or response examples available — actual payload format is unknown
- —Platform legitimacy and data source provenance are unverifiable from available materials
Citations
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge for /api/v1/messages/135 specifies maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/messages/135
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com