Pay-per-request API suite on Base (USDC) via x402 — $0.02/call, no API keys required.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. The specific endpoint at `/api/v1/products/42` is labeled "Premium API Access" and accepts POST requests, settling payments in USDC (contract 0x8335…2913) on Base. The x402 challenge advertises a maximum amount of 20,000 base units, which at 6 decimals for USDC equals $0.02 per request.
The broader platform offers endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are listed at the same $0.02/request price point.
The platform emphasizes simplicity: no API keys, no rate limits, no minimum commitments, and instant access. Payments are made per-call using the x402 exact-payment scheme. Documentation pages beyond the landing page appear to require a wallet connection and contain no additional readable content.
Capabilities
Use cases
- —Accessing premium API data with per-call USDC micropayments on Base
- —Agent-driven workflows that need on-demand API access without pre-registration
- —Programmatic access to a multi-category API suite (analytics, AI, finance, utilities) with no subscription
Fit
Best for
- —Developers or agents wanting zero-signup, pay-as-you-go API access
- —x402-compatible clients on the Base network
- —Low-volume or bursty workloads where per-request pricing is economical
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume consumers who would benefit from bulk/subscription pricing
Quick start
# The endpoint returns 402 with an x402 challenge.
# Use an x402-compatible client to pay $0.02 USDC on Base per call.
curl -X POST https://lowpaymentfee.com/api/v1/products/42 \
-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 network. However, there is no OpenAPI schema, no request/response examples, and documentation pages are empty (wallet-gated). The specific purpose of /api/v1/products/42 ('Premium API Access') is not explained beyond its title, making it effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown.
- —Documentation, pricing, API, and README pages all render only 'Connect wallet' with no readable content.
- —The specific functionality of /api/v1/products/42 is unclear; 'Premium API Access' is a generic label.
- —No request body schema or response examples could be obtained.
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units in USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/42
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/products/42
- —Platform offers endpoints in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com