Pay-per-call API key generation on Base via x402, settled in USDC at $0.02/request.
What it does
lowpaymentfee.com hosts a collection of pay-per-request API endpoints accessible via the x402 payment protocol on the Base network. The specific endpoint at `/api/v1/apikeys/22` is labeled "Premium API Access" and accepts POST requests with an x402 payment header. Payment is settled in USDC (contract 0x8335…2913 on Base) using the "exact" scheme, with a maximum amount of 20,000 base units — equivalent to $0.02 USD (USDC uses 6 decimals). No API keys, subscriptions, or rate limits are advertised; callers pay per request.
The broader platform advertises additional endpoint categories including 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 endpoint being listed here (`/api/v1/apikeys/22`) is described only as "Premium API Access" with no further documentation on what it returns or what input it expects beyond a POST body.
Documentation is extremely thin — the /docs, /api, /pricing, and /README pages all render only a "Connect wallet" prompt with no substantive content. There is no OpenAPI spec, no request/response schema, and no usage examples available from the crawl. The endpoint is confirmed live (402 challenge captured), but the actual functionality behind "Premium API Access" is unclear from available materials.
Capabilities
Use cases
- —Acquiring API access credentials via a single micropayment
- —Agent-driven pay-per-call API consumption without pre-registration
- —Programmatic access to premium endpoints using x402 on Base
Fit
Best for
- —Agents or bots that need instant API access without signup
- —Developers wanting to test x402 payment flows on Base
- —Use cases requiring no-commitment, pay-as-you-go API access
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —High-volume consumers 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/apikeys/22 \
-H "X-PAYMENT: <x402-payment-token>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge and clear pricing ($0.02 USDC on Base). However, there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples. The actual functionality of 'Premium API Access' is undefined in available materials.
Warnings
- —No OpenAPI or schema documentation available — actual request/response format is unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —The purpose of 'Premium API Access' at /api/v1/apikeys/22 is not explained; it is unclear what this endpoint returns
- —No rate limit or uptime guarantees documented
Citations
- —Endpoint returns 402 with x402 challenge, confirming it is livehttps://lowpaymentfee.com/api/v1/apikeys/22
- —Payment is 20,000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base, equaling $0.02https://lowpaymentfee.com/api/v1/apikeys/22
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Additional endpoint categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com