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 at `/api/v1/payments/46` is listed as "Premium API Access" and returns a standard x402 402 challenge requesting up to 20,000 base units of USDC (0.02 USD) per call. No API keys or rate limits are required; callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises multiple API 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 endpoints are uniformly priced at $0.02 per request.
However, the specific endpoint `/api/v1/payments/46` is labeled only as "Premium API Access" with no documentation on what it actually returns. The docs, pricing, API, and README pages all render as minimal wallet-connect stubs with no substantive content. There is no OpenAPI schema, no request/response examples, and no description of input parameters or output format beyond the x402 challenge's `mimeType: application/json`. The endpoint is confirmed live (402 challenge captured), but the lack of documentation makes it difficult to know what data or service this particular endpoint provides.
Capabilities
Use cases
- —Accessing premium API data without needing API key registration
- —Making one-off API calls paid directly in USDC on Base
- —Agent-driven API consumption with per-request crypto payments
Fit
Best for
- —Developers who want keyless, pay-as-you-go API access
- —AI agents that can settle x402 payments autonomously
- —Users already holding USDC on the Base network
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —Anyone without a Base-network USDC wallet
- —High-volume consumers who need bulk pricing or subscriptions
Quick start
# The endpoint returns HTTP 402 with an x402 challenge.
# Attach a valid X-PAYMENT header (x402 protocol) to pay $0.02 in USDC on Base.
curl -X POST https://lowpaymentfee.com/api/v1/payments/46 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>"Endpoint
Quality
The endpoint is confirmed live via a valid x402 402 challenge, but there is zero documentation on what this specific endpoint does, what inputs it accepts, or what it returns. No OpenAPI schema, no examples, and the docs pages are empty wallet-connect stubs. The listing is effectively a stub.
Warnings
- —No documentation available — docs, pricing, API, and README pages all render as empty wallet-connect screens
- —The specific function of /api/v1/payments/46 ('Premium API Access') is completely undocumented
- —No OpenAPI schema or request/response examples provided
- —No information on what data or service this endpoint actually delivers
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (0.02 USD) on Base networkhttps://lowpaymentfee.com/api/v1/payments/46
- —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/payments/46
- —Available API categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com