Pay-per-call API platform on Base network via x402 — $0.02/request, no API keys required.
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 via the x402 payment protocol. There are no API keys, no rate limits, and no subscription commitments — callers simply attach an X-PAYMENT header with a valid x402 payment proof to access any endpoint.
The specific endpoint at `/api/v1/transactions/362` is listed as "Premium API Access" and returns `application/json`. Based on the x402 challenge, it accepts POST requests and charges a maximum of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The broader platform advertises categories including: metrics and reports APIs, data export and insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation utilities.
Documentation is extremely sparse — the /docs, /pricing, /api, 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 crawl. The endpoint is confirmed live (402 challenge captured), but without documentation it is difficult to know what request body this specific transactions endpoint expects or what it returns.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto prices, exchange rates, and gas estimates via micropayments
- —Running data analytics queries and exporting data on a per-request payment basis
- —Using utility services like geocoding, validation, and conversion with zero setup
Fit
Best for
- —Developers who want instant API access without signup or API key provisioning
- —Agent-based workflows that can settle USDC micropayments on Base via x402
- —Low-volume or bursty usage patterns where $0.02/request flat pricing is economical
Not for
- —High-volume production workloads where per-request costs would accumulate significantly
- —Users who need detailed API documentation, SDKs, or guaranteed SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/362 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, and the landing page describes the platform's catalog and pricing. However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and no examples. The specific purpose of /api/v1/transactions/362 is unclear beyond the generic label 'Premium API Access'.
Warnings
- —No OpenAPI spec or machine-readable schema available
- —All documentation pages (/docs, /pricing, /api, /README) render only 'Connect wallet' with no content
- —The specific purpose and expected request body for /api/v1/transactions/362 is undocumented
- —No response examples or error handling documentation found
- —Cannot verify what data or service this specific endpoint actually provides
Citations
- —The platform charges $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The x402 challenge for this endpoint specifies maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/362
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com