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 exposes a broad catalog of 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 priced at $0.02 per request, payable in USDC on the Base network via the x402 protocol — no API keys, no rate limits, and no upfront commitments.
The specific endpoint `/api/v1/messages/77` is listed as "Premium API Access" and was probed live, returning a valid 402 challenge. Its `maxAmountRequired` is 20000 base units of USDC (6 decimals), which equals $0.02. Payment is settled on-chain to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using the "exact" scheme with a 300-second timeout. The endpoint accepts HTTP POST and returns `application/json`.
Documentation beyond the landing page is sparse — the /api, /pricing, and /README routes all resolve to a "Connect wallet" prompt with no additional content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples. The purpose of the `/api/v1/messages/77` path specifically (as opposed to the other listed endpoints) is unclear; it may be a generic message or content retrieval endpoint, but this is not documented.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time financial data such as token quotes, gas estimates, and exchange rates
- —Running utility operations like geocoding, validation, and data conversion on a per-call basis
- —Integrating pay-per-use data analytics and reporting into agent workflows
Fit
Best for
- —Agents or developers wanting zero-signup, pay-per-call API access
- —Lightweight, low-cost AI inference tasks ($0.02/call)
- —Quick prototyping without rate limits or subscription commitments
Not for
- —High-volume production workloads where $0.02/call adds up significantly
- —Users who need detailed API documentation, SDKs, or guaranteed SLAs
- —Applications requiring non-USDC or non-Base-network payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/77 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no OpenAPI spec, no request/response schema, no usage examples, and the specific purpose of /api/v1/messages/77 is undocumented. The landing page lists many endpoints but provides no detail on inputs or outputs for any of them.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The specific purpose of /api/v1/messages/77 ('Premium API Access') is not explained anywhere
- —All sub-pages (/api, /pricing, /README) return only a 'Connect wallet' prompt with no useful content
- —No request body schema or response examples are documented
Citations
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The endpoint /api/v1/messages/77 returns a 402 challenge with maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/messages/77
- —Categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com