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/32` 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 subscriptions are required — each request is paid individually via the x402 payment protocol.
The platform advertises four categories of APIs: 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/request pricing. The x402 challenge for this endpoint was successfully captured, confirming it is live and accepting payments to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using USDC (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`) on Base.
Note that while the landing page lists many endpoints, the specific functionality behind `/api/v1/keys/32` ("Premium API Access") is not clearly documented — it may serve as a key-generation or access-provisioning endpoint. No OpenAPI schema, request/response examples, or detailed documentation were found for any of the endpoints.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without subscription
- —Fetching real-time financial data like token prices, exchange rates, and gas estimates on a per-call basis
- —Running data analytics queries and exporting reports with no upfront commitment
- —Using utility services like geocoding, validation, and conversion paid per request
Fit
Best for
- —Agents or developers who want instant API access without signup or API keys
- —Low-volume or bursty workloads where per-request pricing is more economical than subscriptions
- —Crypto-native applications already operating on the Base network with USDC
Not for
- —High-volume production workloads where per-request costs would accumulate significantly
- —Users who need detailed SLAs, uptime guarantees, or enterprise support
- —Developers who require comprehensive API documentation and typed schemas before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/32 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02/request in USDC on Base), but there is no OpenAPI schema, no request/response examples, and no documentation for what /api/v1/keys/32 actually returns. The crawled pages beyond the landing page were empty (wallet-connect prompts only). This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The specific purpose of /api/v1/keys/32 ('Premium API Access') is unclear — it may be a key provisioning endpoint rather than a data endpoint
- —No request or response examples found anywhere in crawled content
- —Pricing and /api pages returned only 'Connect wallet' with no useful content
Citations
- —The endpoint returns a 402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/keys/32
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/keys/32
- —All listed endpoints are priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —Platform offers Data & Analytics, AI & ML, Finance & Web3, and Infrastructure API categorieshttps://lowpaymentfee.com