Pay-per-call API platform on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network. There are no API keys, no rate limits, and no minimum commitments — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/customers/41` is listed as "Premium API Access" and returns `application/json` via POST. Its x402 challenge advertises a max amount of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The platform also hosts endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation — all at the same $0.02 price point. Documentation pages exist but appear gated behind a wallet connection, so detailed request/response schemas are not publicly available.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification) without API key management
- —Fetching real-time crypto token quotes and gas estimates programmatically
- —Running geocoding or data validation as a utility microservice with per-call billing
- —Exporting analytics data or generating insights reports on a pay-as-you-go basis
Fit
Best for
- —AI agents that need frictionless, keyless API access with crypto micropayments
- —Developers prototyping multi-service workflows without subscription commitments
- —Web3-native applications already operating on the Base network
Not for
- —High-volume production workloads where per-request pricing adds up quickly
- —Users who need detailed SLAs, rate-limit guarantees, or enterprise support
- —Callers without access to USDC on Base for payment settlement
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/customers/41 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base). However, the specific endpoint's purpose ("Premium API Access" for /customers/41) is vague, no request/response schemas are documented, and all doc pages beyond the landing page are gated behind wallet connection, leaving functionality largely unknown.
Warnings
- —The purpose of /api/v1/customers/41 ('Premium API Access') is unclear — no schema or documentation describes what this endpoint actually returns.
- —All documentation, pricing, and README pages appear gated behind a wallet connection and contain no public content.
- —No OpenAPI spec, request body schema, or response schema is available for any endpoint.
- —The broad catalog of endpoints (AI, finance, utils) is listed on the homepage but none have been individually verified beyond the customers/41 probe.
Citations
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categories, all at $0.02/requesthttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access, Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/customers/41
- —Payment address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with 300-second timeouthttps://lowpaymentfee.com/api/v1/customers/41