Pay-per-call API platform on Base network via x402 — $0.02/request in USDC, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints across data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are priced at $0.02 per request, paid in USDC on the Base network via the x402 protocol. No API keys, accounts, or rate limits are advertised — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The specific endpoint at `/api/v1/payments/14` is listed as "Premium API Access" and returns a 402 challenge requesting up to 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 POST requests and returns application/json.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 price point. However, documentation pages (docs, pricing, README) returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints are undocumented in the crawled material.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto token quotes, gas estimates, and exchange rates on a per-call basis
- —Running geocoding, validation, or data conversion tasks with instant pay-per-use billing
- —Exporting analytics data or generating insights reports without subscription commitments
Fit
Best for
- —Agents and bots that need frictionless, keyless API access via crypto micropayments
- —Developers prototyping with multiple API categories without managing separate subscriptions
- —Web3-native applications that already hold USDC on Base
Not for
- —High-volume production workloads where per-request pricing at $0.02 adds up significantly
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
- —Teams without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/14 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no OpenAPI schema, no documentation of request/response formats, and all docs pages returned only 'Connect wallet' with no content. The actual functionality behind 'Premium API Access' at /api/v1/payments/14 is unclear — it doesn't map to any of the named endpoints on the landing page. Effectively a stub listing.
Warnings
- —Documentation pages (/docs, /pricing, /README, /api) all returned only 'Connect wallet' with no substantive content
- —The endpoint path /api/v1/payments/14 does not correspond to any of the named endpoints listed on the homepage — its actual functionality is unknown
- —No request or response schema is available; callers cannot know what to send or expect back
- —No OpenAPI spec or ai-plugin manifest was found
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, scheme exact, 300s timeouthttps://lowpaymentfee.com/api/v1/payments/14
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com