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 infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no upfront commitments. The x402 payment challenge is confirmed live: callers receive a 402 response with an exact-scheme challenge specifying the USDC contract on Base (0x8335…2913) and a maxAmountRequired of 20000 base units (i.e., $0.02 given USDC's 6 decimals).
The specific endpoint `/api/v1/transactions/189` is listed as "Premium API Access" and accepts HTTP POST. The site advertises additional endpoint families including 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, documentation beyond the landing page is essentially empty (all sub-pages just show "Connect wallet"), so request/response schemas for individual endpoints are not documented. Without concrete input/output schemas or example payloads, it is unclear what data this particular transactions endpoint returns or what POST body it expects.
Capabilities
Use cases
- —Accessing real-time financial data (prices, exchange rates, gas estimates) without API key management
- —Running AI inference tasks (sentiment, summarization, classification, embeddings) on a per-call payment basis
- —Geocoding and data validation utilities paid per request via crypto
Fit
Best for
- —Developers who want zero-signup, pay-as-you-go API access
- —Agents and bots that can settle x402 payments in USDC on Base
- —Low-volume or bursty workloads where subscription pricing is wasteful
Not for
- —High-volume production workloads where $0.02/request adds up quickly
- —Users who need detailed API documentation and guaranteed SLAs before integrating
Quick start
# 1. POST to the endpoint — you'll get a 402 with payment challenge
curl -X POST https://lowpaymentfee.com/api/v1/transactions/189
# 2. Pay the x402 challenge (20000 base units USDC on Base = $0.02)
# then re-send with X-PAYMENT header containing the signed payment proofEndpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no documentation, no OpenAPI spec, no request/response schemas, and all doc pages are empty. The specific purpose of /api/v1/transactions/189 is unknown beyond the label 'Premium API Access'. This is effectively a stub listing.
Warnings
- —All documentation pages (/docs, /api, /pricing, /README) return only 'Connect wallet' with no actual content
- —No OpenAPI or schema available — request body and response format for this endpoint are completely unknown
- —The endpoint path '/api/v1/transactions/189' with description 'Premium API Access' does not match any of the advertised endpoint categories on the landing page, making its purpose unclear
- —No examples or sample payloads available anywhere in the crawled material
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 is live with maxAmountRequired of 20000 base units USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/189
- —Endpoint categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com