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 variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, payable in USDC on the Base network via the x402 payment protocol. No API keys, accounts, or rate limits are advertised — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/62` 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 essentially empty (all sub-pages just show "Connect wallet"), so the actual behavior, request schemas, and response formats for each endpoint are unknown. The specific functionality behind the `/api/v1/transactions/62` path is not documented.
Capabilities
Use cases
- —Accessing paid 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 pay-as-you-go API access
Fit
Best for
- —Developers or agents wanting zero-signup API access via crypto micropayments
- —Testing x402 payment protocol integrations
- —Low-volume, on-demand API consumption without subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs
- —High-volume use cases where per-request pricing at $0.02 adds up quickly
- —Users without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/62 \
-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 pricing and payment details. However, there is no documentation for request/response schemas, no OpenAPI spec, and all doc pages are empty. The purpose of the specific /api/v1/transactions/62 endpoint is unclear beyond the generic label 'Premium API Access'.
Warnings
- —No documentation available — all doc/pricing/API pages return only 'Connect wallet' with no content
- —The specific functionality of /api/v1/transactions/62 is undocumented; 'Premium API Access' is a generic label
- —No request or response schema is provided; callers cannot know what to send or expect back
- —No OpenAPI specification or machine-readable API description found
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, equaling $0.02https://lowpaymentfee.com/api/v1/transactions/62
- —Platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com