Pay-per-call API platform on Base (USDC) — $0.02/request, 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, and infrastructure utilities. Every call costs $0.02 in USDC on the Base network, settled via the x402 payment protocol — no API keys, no subscriptions, no rate limits.
The specific endpoint `/api/v1/inbox/94` is listed as "Premium API Access" and accepts POST requests. 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. Payment is made 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 data generation — all at the same $0.02 per request price point. However, the exact functionality behind the `/api/v1/inbox/94` path is not documented beyond the generic "Premium API Access" label, so its specific input/output behavior is unclear.
Capabilities
Use cases
- —Accessing pay-per-use API services without managing API keys or subscriptions
- —Making micropayment-gated API calls settled in USDC on Base
- —Integrating agent-purchasable endpoints into automated workflows
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users who prefer crypto-native micropayments over traditional billing
Not for
- —Users needing detailed documentation or guaranteed SLAs for production workloads
- —Anyone without a Base-compatible USDC wallet
- —Use cases requiring free or bulk-discounted API access
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/inbox/94 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base). However, the specific functionality of /api/v1/inbox/94 is undocumented — no input schema, no output schema, no example responses, and no explanation of what 'Premium API Access' actually does. The broader site lists many endpoints but provides no API documentation beyond names and prices.
Warnings
- —The exact purpose and input/output schema of /api/v1/inbox/94 are unknown — 'Premium API Access' is not described anywhere in the crawled content.
- —No OpenAPI spec, no detailed docs, and /api, /pricing, /README pages all returned only a 'Connect wallet' prompt with no useful content.
- —The platform lists many endpoint categories (AI, finance, analytics, etc.) but none have visible documentation — functionality is unverifiable.
Citations
- —The platform advertises $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The x402 challenge for /api/v1/inbox/94 shows maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base.https://lowpaymentfee.com/api/v1/inbox/94
- —The platform lists endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com