Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utilities at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection 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/messages/49` is listed as "Premium API Access." Its x402 challenge advertises a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts HTTP POST and returns `application/json`.
The broader platform advertises additional endpoints including 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 per-call price point. However, no OpenAPI schema, detailed documentation, or example request/response payloads were found during crawling; the /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto quotes, gas estimates, or exchange rates with per-call payment
- —Geocoding or data validation as a utility microservice in automated pipelines
- —Exporting data or generating analytics reports on a pay-as-you-go basis
Fit
Best for
- —AI agents that need keyless, pay-per-call access to diverse utility endpoints
- —Developers prototyping with minimal setup — no signup, no rate limits
- —Web3-native applications already operating on the Base network
Not for
- —High-volume production workloads where $0.02/request adds up significantly
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/messages/49 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no documentation beyond a landing page listing, no example requests or responses, and the /api, /pricing, and /README pages are all empty (wallet-connect only). The specific purpose of /api/v1/messages/49 is entirely opaque.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The specific endpoint /api/v1/messages/49 has no description beyond 'Premium API Access' — its actual functionality is unknown
- —All documentation pages (/api, /pricing, /README) returned only a 'Connect wallet' prompt with no content
- —No example request or response payloads are available; callers must guess at the expected input format
Citations
- —The platform lists endpoints across data & analytics, AI & ML, finance & Web3, and infrastructure categories, all priced 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 with exact scheme and 300s timeouthttps://lowpaymentfee.com/api/v1/messages/49