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 via the x402 payment protocol. No API keys, accounts, or rate limits are required — callers simply attach an X-PAYMENT header with a valid payment proof to access any endpoint.
The specific endpoint at `/api/v1/transactions/188` is listed as "Premium API Access" and returns `application/json`. Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts HTTP POST and is discoverable. The payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform advertises 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 (docs, pricing, README) were largely empty during crawl, returning only a "Connect wallet" prompt, so the actual request/response schemas for individual endpoints are unknown.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification) without managing API keys
- —Fetching real-time crypto token quotes or gas estimates with per-call USDC micropayments
- —Geocoding or data validation as a utility service paid per request on Base
Fit
Best for
- —Developers or agents wanting zero-signup, pay-as-you-go API access
- —Use cases requiring very small per-call costs ($0.02) settled on-chain
- —Projects already operating on the Base L2 network with USDC
Not for
- —High-volume workloads where $0.02/request adds up and bulk pricing is needed
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —Callers without a Base-compatible wallet or USDC balance
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/188 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI schema, no request/response examples, and all documentation pages returned only 'Connect wallet' with no substantive content. The purpose of this specific /transactions/188 path is unclear beyond the generic 'Premium API Access' label.
Warnings
- —Documentation pages (/docs, /pricing, /README) are effectively empty — only showing 'Connect wallet'
- —No request or response schema available for any endpoint
- —The specific purpose of /api/v1/transactions/188 is unclear; it may be a generic or placeholder endpoint
- —The broad catalog of advertised endpoints (AI, finance, geo, etc.) could not be verified for actual functionality
Citations
- —Platform advertises endpoints across data, AI, finance, 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 Basehttps://lowpaymentfee.com/api/v1/transactions/188
- —Payment address is 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with 300-second timeouthttps://lowpaymentfee.com/api/v1/transactions/188