Pay-per-call API platform on Base network via x402 — $0.02/request in USDC, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, paid in USDC on the Base network. The x402 protocol means there are no API keys, no accounts, and no rate limits — callers simply attach a payment header to each request.
The specific endpoint at `/api/v1/payments/297` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 price point. However, documentation beyond the landing page is extremely sparse; the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled content.
Capabilities
Use cases
- —Accessing premium API endpoints without creating accounts or managing API keys
- —Making one-off API calls with per-request USDC micropayments on Base
- —Agent-driven workflows that need frictionless, key-free API access
Fit
Best for
- —Developers who want zero-signup, pay-as-you-go API access
- —AI agents that need to autonomously purchase API calls via x402
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who want bulk pricing or subscription discounts
- —Developers without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/297 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it works. However, documentation is essentially nonexistent — docs/pricing/API/README pages all show only 'Connect wallet'. There is no OpenAPI spec, no request/response schema, and no examples. The purpose of this specific '/payments/297' endpoint beyond 'Premium API Access' is unclear.
Warnings
- —Documentation pages (docs, pricing, API, README) are all empty beyond a 'Connect wallet' prompt — no technical details available.
- —No OpenAPI or schema documentation exists for any endpoint.
- —The specific functionality of /api/v1/payments/297 ('Premium API Access') is not described anywhere — it is unclear what data or service it returns.
- —The broader platform lists many endpoint categories (AI, finance, analytics, etc.) but none have documented request/response formats.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base with exact scheme and 300s timeouthttps://lowpaymentfee.com/api/v1/payments/297
- —Platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs