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. All endpoints are pay-per-request at $0.02 each, settled in USDC on the Base network. No API keys, rate limits, or subscriptions are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/302` is listed as "Premium API Access" and its x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
The broader platform advertises additional endpoints 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 extremely thin: the /docs, /pricing, /api, and /README pages all returned only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The actual functionality behind this specific `/api/v1/transactions/302` endpoint and what data it returns is unclear from the available material.
Capabilities
Use cases
- —Accessing premium API data without needing API keys or subscriptions
- —Making one-off paid API calls settled in USDC on Base
- —Agent-driven workflows that need frictionless pay-per-use endpoints
Fit
Best for
- —Developers who want zero-signup, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on Base network
Not for
- —Users needing detailed API documentation or request/response schemas before integrating
- —High-volume callers who would benefit from bulk pricing or subscriptions
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/302 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming it accepts payments. However, there is no OpenAPI spec, no documented request/response schema, no examples, and the docs/pricing/README pages are all empty stubs. The actual functionality of this specific endpoint (/api/v1/transactions/302) is entirely unclear — 'Premium API Access' is a generic label with no description of what data or service it provides.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (/docs, /pricing, /api, /README) returned only 'Connect wallet' with no content
- —The purpose and functionality of /api/v1/transactions/302 ('Premium API Access') is not described anywhere
- —The broad catalog of endpoints listed on the homepage cannot be verified for actual functionality
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/302
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transactions/302