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/120`) is labeled "Premium API Access" and accepts POST requests. Payment is settled in USDC (contract 0x8335…2913 on Base) with a maximum amount of 20,000 base units, which equals $0.02 per call (USDC uses 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.
Documentation is extremely sparse — the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled material. The endpoint is confirmed live (returns a proper 402 challenge), but the actual behavior behind the paywall and the response format for `/api/v1/payments/120` specifically are unknown.
Capabilities
Use cases
- —Accessing premium API data without requiring API key registration
- —Making one-off paid API calls settled instantly in USDC on Base
- —Integrating pay-per-use endpoints into autonomous agent workflows
Fit
Best for
- —Developers who want instant API access without signup or API keys
- —Agent-based systems that can settle x402 payments programmatically
- —Users already holding USDC on the Base network
Not for
- —Users who need detailed API documentation or response schemas before integrating
- —Anyone without a Base-compatible wallet or USDC balance
- —High-volume consumers who need bulk pricing or subscription plans
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/payments/120 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is confirmed live with a valid 402 challenge and clear pricing ($0.02 USDC on Base). However, documentation is essentially nonexistent — no OpenAPI spec, no request/response schemas, no examples, and the specific purpose of /api/v1/payments/120 is unclear beyond the generic label 'Premium API Access'. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, /api, and /README all render only 'Connect wallet' with no technical content
- —No OpenAPI or schema definition found for any endpoint
- —The specific purpose and response format of /api/v1/payments/120 is unknown — 'Premium API Access' is a generic label
- —Cannot verify what data or service is actually returned behind the paywall
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC payment on Base networkhttps://lowpaymentfee.com/api/v1/payments/120
- —maxAmountRequired is 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), equaling $0.02https://lowpaymentfee.com/api/v1/payments/120
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform lists endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Documentation pages (/docs, /pricing, /api, /README) render only 'Connect wallet' with no further contenthttps://lowpaymentfee.com/docs