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 catalog 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 with no API keys, no rate limits, and no commitments required. The x402 payment challenge is handled inline: callers attach an X-PAYMENT header with a signed USDC payment to unlock each request.
The specific endpoint at `/api/v1/transfers/77` is listed under the title "Premium API Access." Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts POST requests and returns application/json. Beyond this, no detailed documentation, request/response schemas, or example payloads are available — the docs, pricing, and README pages all resolve to a minimal "Connect wallet" stub.
The broader 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 — all at the same $0.02 price point. However, no OpenAPI spec, detailed endpoint documentation, or sample responses were found during the crawl, so the actual behavior and output format of each endpoint remain unverified.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API keys
- —Programmatic access to analytics, AI inference, or financial data with per-call USDC payments
- —Testing x402 payment flows on Base network
Fit
Best for
- —Developers wanting zero-signup, pay-as-you-go API access
- —AI agents with USDC wallets on Base that need diverse utility endpoints
- —Prototyping x402 payment integrations
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where per-request crypto payments add latency
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/77 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no example payloads. The specific purpose of /api/v1/transfers/77 ('Premium API Access') is entirely opaque.
Warnings
- —No OpenAPI or schema documentation available — endpoint behavior is unverified
- —Docs, pricing, and README pages all render only a 'Connect wallet' stub with no actual content
- —The purpose and expected input/output of /api/v1/transfers/77 is undocumented
- —The broad catalog of endpoints (AI, finance, analytics, etc.) is advertised but none have verifiable documentation
Citations
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transfers/77
- —Platform advertises endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com