Pay-per-request premium API access via x402 on Base, settled in USDC at $0.02/call.
What it does
lowpaymentfee.com is an x402-enabled API platform offering a broad catalog of pay-per-request endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, payable in USDC on the Base network with no API keys, no rate limits, and no minimum commitments required. The x402 protocol handles payment inline: callers attach an X-PAYMENT header to each request and the server fulfills the call once payment is verified.
The specific endpoint at `/api/v1/charges/124` is listed as "Premium API Access" and returns an x402 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 beyond the landing page is extremely sparse; the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There are no OpenAPI specs, request/response schemas, or usage examples available from the crawled content.
Capabilities
Use cases
- —Accessing premium API endpoints without traditional API key registration
- —Making one-off paid API calls from autonomous agents using x402 protocol
- —Integrating pay-per-request data or AI services into workflows settled on Base
Fit
Best for
- —Agents or developers who want zero-signup, pay-as-you-go API access
- —x402-compatible clients that can attach inline USDC payments on Base
- —Low-volume or sporadic API consumers who don't want subscriptions
Not for
- —Users who need detailed API documentation or OpenAPI schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or rate-limited tiers
- —Users without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/124 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema documentation, no examples, and all doc pages render only 'Connect wallet'. The specific purpose of /api/v1/charges/124 beyond 'Premium API Access' is unclear.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no usable content
- —The specific functionality of /api/v1/charges/124 is not described beyond the generic label 'Premium API Access'
- —The broader platform lists many endpoints but none have documented input/output schemas
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 with exact scheme and 300s timeouthttps://lowpaymentfee.com/api/v1/charges/124
- —Platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com