Pay-per-call API platform on Base via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. Every endpoint is priced at $0.02 per request, paid in USDC on the Base network using the x402 payment protocol. There are no API keys, no rate limits, and no subscription commitments — callers simply attach an X-PAYMENT header with a valid x402 payment proof to each request.
The specific endpoint at `/api/v1/payments/256` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0.02 USD, since USDC uses 6 decimals) on Base. The payment is settled to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` with a 300-second timeout. The endpoint accepts POST requests and returns `application/json`.
The broader platform advertises categories including metrics, reports, data export, insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation. However, documentation beyond the landing page is essentially empty (all sub-pages only show "Connect wallet"), so the actual behavior, request schemas, and response formats for any of these endpoints are unknown. Without documentation or example payloads, the real capabilities of this specific endpoint cannot be verified.
Capabilities
Use cases
- —Accessing premium API functionality with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 payment protocol integrations against a live endpoint
Fit
Best for
- —Developers experimenting with x402 payment flows
- —Agents needing keyless API access with crypto micropayments
- —Low-volume, on-demand API consumption without subscriptions
Not for
- —Users who need detailed API documentation or well-defined request/response schemas
- —High-volume production workloads where $0.02/request adds up significantly
- —Users without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/256 \
-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 documentation, no OpenAPI schema, no request/response examples, and no explanation of what this specific endpoint actually does beyond the generic label 'Premium API Access'. All doc pages return only 'Connect wallet' with no content.
Warnings
- —No documentation available — all doc/pricing/API pages are empty stubs showing only 'Connect wallet'
- —No request or response schema provided for this endpoint; actual functionality is unknown
- —The endpoint name 'Premium API Access' is generic and does not describe what the endpoint does
- —Cannot verify what data or service is actually returned upon successful payment
Citations
- —Endpoint returns 402 with x402 challenge requesting 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/256
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/payments/256
- —Platform offers endpoints across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com