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 collection 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 protocol handles payment inline: callers attach a payment header to each HTTP request and receive the response immediately upon settlement.
The specific endpoint at `/api/v1/transfers/157` is listed as "Premium API Access" and returns an x402 challenge requesting up to 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`. The platform advertises additional endpoints across four categories: Data & Analytics (metrics, reports, 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).
Documentation is extremely sparse — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled material. The endpoint is live (402 challenge confirmed), but without documentation it is unclear what input this particular `/transfers/157` endpoint expects or what it returns.
Capabilities
Use cases
- —Accessing data analytics and reports on a per-request payment basis without API key management
- —Running AI inference tasks (sentiment analysis, summarization, classification, embeddings) with per-call USDC payments
- —Fetching real-time financial data such as token quotes, exchange rates, and gas estimates
- —Using utility services like geocoding, validation, and data conversion via micropayments
Fit
Best for
- —Developers who want instant API access without signup or subscription
- —Agent-based workflows that can attach x402 payment headers automatically
- —Low-volume or bursty usage patterns where pay-per-call is more economical than a subscription
Not for
- —High-volume production workloads where per-request pricing at $0.02 adds up quickly
- —Users who need detailed API documentation, SDKs, or guaranteed SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/157 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing, but documentation is effectively nonexistent — all doc pages show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, and no examples. The purpose of the specific /transfers/157 endpoint is unclear beyond its generic 'Premium API Access' label.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) contain no usable content — only a 'Connect wallet' prompt.
- —No OpenAPI or schema documentation is available; request and response formats for /api/v1/transfers/157 are unknown.
- —The purpose and behavior of the /transfers/157 endpoint specifically is undocumented; the 'Premium API Access' label is generic.
- —The broader platform lists many endpoints but none have documented input/output schemas.
Citations
- —The endpoint returns an x402 challenge requesting maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transfers/157
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transfers/157
- —Platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com