Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/transfers/165` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
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 priced at $0.02 per request.
This particular endpoint (`/api/v1/transfers/165`) is labeled "Premium API Access" but its actual functionality is not documented beyond that label. The crawled docs, pricing, API, and README pages all returned only a "Connect wallet" prompt with no additional content. Without further documentation or example responses, the specific behavior of this endpoint remains unclear.
Capabilities
Use cases
- —Accessing premium API data without traditional API key registration
- —Making one-off API calls paid directly in USDC on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
Fit
Best for
- —Developers who want to avoid API key management and subscriptions
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation and response schemas before integrating
- —High-volume callers who would benefit from bulk pricing or subscription plans
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/165 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, but there is no documentation, no OpenAPI schema, no example requests or responses, and the actual functionality behind "Premium API Access" is undefined. The docs/pricing/README pages are all blank beyond a wallet-connect prompt.
Warnings
- —The specific functionality of /api/v1/transfers/165 ('Premium API Access') is not documented anywhere in the crawled material.
- —All documentation pages (docs, pricing, README, api) returned only 'Connect wallet' with no usable content.
- —No OpenAPI spec, request schema, or response schema is available.
- —The endpoint path '/api/v1/transfers/165' with a numeric ID suggests it may be a dynamic or user-specific resource rather than a general-purpose API.
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC ($0.02) on Base networkhttps://lowpaymentfee.com/api/v1/transfers/165
- —The platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transfers/165
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com