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 hosts a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general utility services. Every endpoint is priced at $0.02 per request, paid in USDC on the Base network via the x402 protocol. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.
The specific endpoint `/api/v1/inbox/95` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) on Base. The payment is settled to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
The platform advertises four categories of APIs: 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). However, the specific functionality behind the `/api/v1/inbox/95` path is not documented — the generic "Premium API Access" label provides no detail on what data or service this particular endpoint returns. No OpenAPI schema, request/response examples, or detailed documentation were found.
Capabilities
Use cases
- —Accessing data analytics and reports on a per-request payment basis
- —Running AI inference tasks (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data and crypto market quotes
- —Using utility services like geocoding, validation, and conversion with instant pay-as-you-go pricing
- —Integrating agent-driven workflows that settle payments automatically via x402
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments autonomously on Base
- —Projects needing low-cost ($0.02) micro-transactions for API calls
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who need bulk/subscription pricing
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/inbox/95 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation for what /api/v1/inbox/95 actually does, no OpenAPI schema, no request/response examples, and the crawled pages beyond the homepage returned only 'Connect wallet' with no useful content. The generic 'Premium API Access' label is uninformative.
Warnings
- —No documentation found for the specific endpoint /api/v1/inbox/95 — its actual functionality is unknown
- —No OpenAPI or schema definition available for any endpoint on the platform
- —The /api, /pricing, and /README pages returned no useful content (only 'Connect wallet')
- —The 'Premium API Access' label is generic and does not describe what the endpoint returns
- —Multiple endpoint categories are advertised but none have documented request/response formats
Citations
- —The platform advertises 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/inbox/95 requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/inbox/95