x402-gated API platform on Base offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-protocol API marketplace that gates access to a variety of endpoints behind per-request micropayments settled in USDC on the Base network. The specific endpoint `/api/v1/products/5` is listed as "Premium API Access" and requires a payment of up to 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals) per call. The platform advertises no API keys, no rate limits, and instant access — callers simply attach an x402 payment header to each request.
The broader platform organizes its endpoints into 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 listed endpoints share the same $0.02 per-request pricing.
The `/api/v1/products/5` endpoint itself is confirmed live via a 402 challenge. However, documentation beyond the landing page is essentially empty (all doc/pricing/API pages just show "Connect wallet"), so the actual request/response schemas for this specific endpoint are unknown. There is no OpenAPI spec, no example payloads, and no detailed documentation available from the crawl. The endpoint accepts POST requests and returns `application/json`.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API key management
- —Programmatic access to data, AI, finance, or utility services with per-call billing
- —Testing x402 payment protocol integrations against a live endpoint
Fit
Best for
- —Developers exploring x402 micropayment-gated APIs
- —AI agents needing keyless, pay-per-use endpoint access
- —Low-volume consumers who want no subscription commitment
Not for
- —High-volume production workloads where $0.02/request adds up significantly
- —Users who need detailed API documentation or guaranteed SLAs before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/5 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge, and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, and all documentation pages are empty beyond the landing page. The purpose of `/api/v1/products/5` specifically is unclear — it could be any of the advertised services or a generic product endpoint. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (docs, pricing, API, README) return only 'Connect wallet' with no useful content
- —The specific purpose of /api/v1/products/5 is not documented; 'Premium API Access' is generic
- —No agents.txt present; no robots.txt found
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/products/5
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/products/5
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com