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 set of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and infrastructure utilities. All endpoints are pay-per-request at $0.02 each, settled in USDC on the Base network. No API keys, no rate limits, and no sign-up required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transfers/135` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base). Since USDC uses 6 decimals, this equates to $0.02 per call, consistent with the site's uniform pricing. Payment is made via the x402 "exact" scheme with a 300-second timeout.
The platform advertises categories including 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 (geocoding, validation, conversion, generation). However, the crawled documentation pages (docs, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints remain undocumented.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification) without managing API keys
- —Fetching real-time crypto prices, gas estimates, or exchange rates with per-call micropayments
- —Geocoding or data validation as a utility service paid per request via x402
- —Exporting analytics data or generating insights on a pay-as-you-go basis
Fit
Best for
- —AI agents needing keyless, pay-per-call access to diverse API endpoints
- —Developers who want to avoid subscription commitments for low-volume API usage
- —Web3-native applications that can settle payments in USDC on Base
Not for
- —High-volume production workloads where per-call pricing at $0.02 adds up quickly
- —Users who need detailed API documentation, response schemas, or SLA guarantees before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/135 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge with clear pricing. However, documentation pages are empty (just 'Connect wallet'), there is no OpenAPI schema, no example requests or responses, and the actual functionality behind '/api/v1/transfers/135' is unclear beyond the generic 'Premium API Access' label. The broad claims about AI, analytics, and finance endpoints cannot be verified from the crawl.
Warnings
- —Documentation pages (/docs, /pricing, /README) contain no usable content — only a 'Connect wallet' prompt
- —No OpenAPI or schema available; request/response formats are unknown
- —The specific endpoint '/api/v1/transfers/135' has a generic description ('Premium API Access') with no indication of what it actually returns
- —The wide range of advertised capabilities (AI, analytics, finance, geocoding) cannot be verified from available crawl data
Citations
- —Uniform pricing of $0.02 per request, no API keys, no rate limitshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base (= $0.02)https://lowpaymentfee.com/api/v1/transfers/135
- —Platform advertises endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transfers/135