Pay-per-call API platform on Base via x402 — $0.02/request, no API keys required.
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 at `/api/v1/payments/95` is labeled "Premium API Access" and charges up to $0.02 per call (20,000 base units of USDC with 6 decimals). 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 listed at $0.02 per request. However, this specific listing is for the `/api/v1/payments/95` endpoint, whose exact functionality beyond "Premium API Access" is not documented in the crawled material.
The endpoint is live and returns a well-formed x402 challenge. Payment settles in USDC on Base to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3`. The docs, pricing, and README pages all returned minimal content (just a "Connect wallet" prompt), so detailed request/response schemas and usage documentation are unavailable.
Capabilities
Use cases
- —Accessing premium API functionality with per-call USDC micropayments on Base
- —Agent-driven workflows that need keyless, on-demand API access
- —Testing x402 protocol integrations with a low-cost endpoint
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —AI agents that need frictionless pay-per-use API access
- —Users who want to avoid API key management and subscriptions
Not for
- —Users needing detailed API documentation or OpenAPI specs before integrating
- —High-volume callers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/95 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, but there is no documentation, no OpenAPI schema, no request/response examples, and the specific functionality of this endpoint is unclear beyond the generic label 'Premium API Access'. Docs pages returned only 'Connect wallet' with no usable content.
Warnings
- —The exact functionality of /api/v1/payments/95 is undocumented — 'Premium API Access' is the only description available.
- —No OpenAPI spec, request schema, or response schema was found.
- —All documentation pages (docs, pricing, README, api) returned only a 'Connect wallet' prompt with no substantive content.
- —The platform lists many endpoint categories (AI, finance, analytics, infrastructure) but none are documented in detail; actual capabilities are unverified.
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/payments/95
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/payments/95