Pay-per-request API collection on Base via x402 — $0.02/call in USDC, no API keys required.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. The specific endpoint at `/api/v1/collections/26` is labeled "Premium API Access" and accepts POST requests, settling payments in USDC (contract 0x8335…2913 on Base). The x402 challenge advertises a maxAmountRequired of 20,000 base units, which at 6 decimals for USDC equals $0.02 per request.
The broader platform offers 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 listed at the same $0.02/request price point.
The platform advertises no API keys, no rate limits, no minimums, and instant access. Payment is handled entirely through the x402 protocol's X-PAYMENT header mechanism on the Base L2 network. Documentation pages beyond the landing page were largely empty (showing only a "Connect wallet" prompt), so details about request/response schemas for individual endpoints are not available from the crawled material.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) with per-call USDC payments
- —Fetching real-time financial data like token quotes, exchange rates, and gas estimates without subscription commitments
- —Running data analytics queries and exporting reports on a pay-as-you-go basis
- —Using utility services like geocoding and validation without managing API keys
Fit
Best for
- —Agents or developers who want instant API access without signup or API key management
- —Low-volume or bursty workloads where per-request pricing is more economical than subscriptions
- —Crypto-native applications already operating on the Base network with USDC
Not for
- —High-volume production workloads where $0.02/request adds up significantly compared to bulk-priced alternatives
- —Users who need detailed API documentation, request/response schemas, or SLA guarantees before integrating
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/collections/26 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'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 documentation for request/response formats, and the /docs, /pricing, /api, and /README pages are all empty beyond a wallet-connect prompt. The specific purpose of `/api/v1/collections/26` ("Premium API Access") is ambiguous — it's unclear what data or functionality it returns. This is effectively a stub listing.
Warnings
- —No API documentation available — all doc pages return only a 'Connect wallet' prompt with no content
- —No request or response schema provided for this endpoint or any other endpoint on the platform
- —The purpose of /api/v1/collections/26 ('Premium API Access') is not explained anywhere in the crawled material
- —Cannot verify what actual data or functionality any of these endpoints provide
Citations
- —The x402 challenge advertises maxAmountRequired of 20000 base units in USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/collections/26
- —All endpoints are listed at $0.02 per request with no API keys, no rate limits, and no minimumshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com