Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad catalog of pay-per-request endpoints settled in USDC on the Base network. The specific endpoint at `/api/v1/keys/88` is listed as "Premium API Access" and costs up to $0.02 per call (20,000 base units of USDC with 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an x402 payment header to each request.
The platform advertises four categories of endpoints: 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 endpoint at `/api/v1/keys/88` does not clearly map to any of the named API categories on the site — it appears to be a generic or premium access key endpoint. There is no OpenAPI schema, no detailed documentation, and no example request/response payloads available from the crawled pages. The x402 challenge confirms the endpoint is live and accepts POST requests with USDC payment on Base, but the actual functionality behind this specific path is unclear.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without subscription
- —Fetching real-time financial data like token quotes, gas estimates, and exchange rates on a per-call basis
- —Running data analytics queries and exporting data with per-request billing
- —Geocoding and data validation as utility microservices
Fit
Best for
- —Agents or developers who want zero-commitment, pay-as-you-go API access
- —Use cases requiring low-cost micropayments per API call ($0.02)
- —Crypto-native workflows already operating on the Base network with USDC
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscription discounts
- —Users without USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/88 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and confirms pricing and payment details, but there is no OpenAPI schema, no documentation beyond a landing page listing, and no example request/response data. The specific endpoint /api/v1/keys/88 has no clear description of what it actually returns. Effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The specific endpoint /api/v1/keys/88 ('Premium API Access') does not correspond to any named API on the landing page — its actual functionality is unknown
- —No example requests or responses are available; integration requires trial-and-error
- —All non-root crawled pages (api, pricing, README) returned only 'Connect wallet' with no useful content
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/keys/88
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/keys/88
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers endpoints in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com