Pay-per-call API platform on Base (USDC) via x402 — $0.02/request, no API keys required.
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 utility services. Every endpoint costs $0.02 per request, paid in USDC on the Base network. The x402 protocol means there are no API keys, no sign-ups, and no rate limits — callers simply attach a payment header to each request.
The specific endpoint at `/api/v1/transfers/112` 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 equals $0.02 per call, consistent with the site's uniform pricing. Payment is made via the x402 "exact" scheme to wallet 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3, with a 300-second timeout.
The platform advertises categories including metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation. However, documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so the actual behavior, request/response schemas, and data sources for each endpoint are unknown. The `/api/v1/transfers/112` endpoint in particular has no documented purpose beyond the generic "Premium API Access" label.
Capabilities
Use cases
- —Agents needing on-demand API access without managing API keys or subscriptions
- —Programmatic access to AI inference (sentiment, summarization, classification, embeddings) with per-call billing
- —Fetching real-time financial data (prices, exchange rates, gas estimates) via crypto micropayments
- —Utility operations like geocoding, validation, and data conversion paid per request
Fit
Best for
- —Developers or agents who want zero-signup, pay-as-you-go API access
- —x402-compatible wallets and agents on the Base network
- —Low-volume or bursty workloads where per-call pricing is more economical than subscriptions
Not for
- —Users who need detailed API documentation, schemas, or SLAs before integrating
- —High-volume production workloads where $0.02/request adds up significantly
- —Users without USDC on Base or an x402-compatible payment client
Quick start
# POST with x402 payment header (pseudocode)
curl -X POST https://lowpaymentfee.com/api/v1/transfers/112 \
-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). However, there is no documentation, no request/response schema, no examples, and the purpose of this specific endpoint (/api/v1/transfers/112) is entirely unclear. All doc/pricing/API sub-pages return only 'Connect wallet' with no content.
Warnings
- —No documentation available — all sub-pages (docs, api, pricing, README) render only 'Connect wallet'
- —The purpose and expected input/output of /api/v1/transfers/112 ('Premium API Access') is undocumented
- —No OpenAPI spec, no request schema, no response schema available
- —Cannot verify what data or functionality any endpoint actually provides
Citations
- —Uniform pricing of $0.02 per request across all endpointshttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units USDC (=$0.02) on Basehttps://lowpaymentfee.com/api/v1/transfers/112
- —Payment asset is USDC at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transfers/112
- —Available API categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com