Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are pay-per-request at $0.02 each, settled in USDC on the Base network. No API keys, accounts, or rate limits are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/products/85` is listed as "Premium API Access" and returns `application/json`. Its x402 challenge advertises a max amount of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, which has 6 decimals), equating to $0.02 per call. Payment is sent to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The platform also advertises AI endpoints (sentiment analysis, text summarization, classification, embeddings), finance endpoints (price feeds, exchange rates, token quotes, gas estimates), data endpoints (metrics, reports, export, insights), and utility endpoints (geocoding, validation, conversion, generation). However, documentation is extremely sparse — the docs, pricing, and API pages all render only a "Connect wallet" prompt with no further detail. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available. It is unclear what inputs the `/api/v1/products/85` endpoint expects or what its response payload contains.
Capabilities
Use cases
- —Accessing various data, AI, finance, and utility APIs without needing an account or API key
- —Making one-off API calls with per-request USDC micropayments on Base
- —Integrating pay-as-you-go API services into autonomous agent workflows
Fit
Best for
- —Developers wanting frictionless, keyless API access via crypto micropayments
- —AI agents that need to purchase API calls programmatically via x402
- —Users who prefer pay-per-use pricing without subscriptions or commitments
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or rate-limited plans
- —Developers without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/products/85 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, confirming pricing and payment details. However, there is no OpenAPI spec, no documentation beyond a landing page listing, no request/response schemas, and no examples. The purpose of the specific /api/v1/products/85 endpoint is unclear beyond the generic label 'Premium API Access'. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or schema documentation available for any endpoint
- —Docs, pricing, API, and README pages all render only 'Connect wallet' with no content
- —The specific purpose and expected input/output of /api/v1/products/85 is undocumented
- —Cannot verify what data or service this endpoint actually provides
Citations
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (6 decimals = $0.02) on Base networkhttps://lowpaymentfee.com/api/v1/products/85
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/products/85
- —Platform offers endpoints across data/analytics, AI/ML, finance/Web3, and infrastructure categorieshttps://lowpaymentfee.com