Pay-per-call premium API access on Base via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. This specific endpoint (`/api/v1/payments/104`) is labeled "Premium API Access" and accepts POST requests. Payment is settled in USDC (contract `0x8335…2913` on Base) at a cost of $0.02 per call (20,000 base units with 6 decimals). No API keys, rate limits, or upfront commitments are required — callers simply attach an `X-PAYMENT` header with a valid x402 payment proof.
The broader lowpaymentfee.com platform advertises 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 listed endpoints share the same $0.02/request pricing. However, the specific functionality behind `/api/v1/payments/104` is not documented beyond the generic "Premium API Access" label, so its exact behavior is unclear.
The x402 challenge is live and well-formed, returning a standard 402 response with version 1 of the protocol. The payment recipient address is `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`, and the maximum timeout for payment settlement is 300 seconds. Documentation pages beyond the landing page returned only a "Connect wallet" prompt with no additional technical detail.
Capabilities
Use cases
- —Accessing premium API functionality without API key registration
- —Making one-off paid API calls settled in USDC on Base
- —Integrating pay-per-request endpoints into agent workflows via x402
Fit
Best for
- —Developers who want instant API access without signup or API keys
- —Agents that can settle x402 payments in USDC on Base
- —Low-volume or sporadic usage where per-call pricing is preferable to subscriptions
Not for
- —Users who need detailed API documentation or schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Callers who cannot settle payments on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/104 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC per request on Base). However, there is no documentation of what this endpoint actually returns, no request/response schema, and no examples. The docs, pricing, and README pages all returned only 'Connect wallet' with no content. The exact purpose of '/api/v1/payments/104' is unknown beyond the generic label.
Warnings
- —The specific functionality of /api/v1/payments/104 is undocumented — 'Premium API Access' is the only description available.
- —All documentation pages (docs, pricing, README, api) returned only a 'Connect wallet' prompt with no technical content.
- —No request or response schema is available; callers cannot know what to send or expect back.
- —The endpoint path '/api/v1/payments/104' does not match any of the named endpoints listed on the landing page, making its purpose unclear.
Citations
- —Endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 in USDC on Basehttps://lowpaymentfee.com/api/v1/payments/104
- —All listed endpoints are priced at $0.02 per request 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/104
- —Platform offers endpoints in Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com