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, rate limits, or subscriptions are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/198` is listed as "Premium API Access" and advertises a max amount of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The x402 challenge confirms the endpoint is live, accepts POST requests, and returns application/json. The payment timeout is 300 seconds.
The broader platform advertises categories including: metrics and reports APIs, data export and insights, sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and generation utilities. However, documentation pages (docs, pricing, README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and response schemas of these endpoints are undocumented in the crawled material.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Programmatic access to utility or data endpoints with per-call USDC micropayments
- —Testing x402 payment protocol integrations on Base network
Fit
Best for
- —Developers or agents wanting zero-signup, pay-as-you-go API access
- —x402 protocol experimentation and integration testing
- —Low-volume, on-demand API calls where subscription pricing is overkill
Not for
- —Users who need detailed API documentation or response schema guarantees before calling
- —High-volume use cases where per-call pricing at $0.02 would be expensive at scale
- —Users without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/198 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and confirms pricing and payment details, but there is no OpenAPI schema, no documented request/response format, and all documentation pages returned only a wallet-connect prompt. The actual functionality behind 'Premium API Access' at /api/v1/transactions/198 is unclear — it could be anything. The listing is essentially a stub with confirmed liveness.
Warnings
- —No API documentation available — all doc pages return only 'Connect wallet' with no content
- —The specific purpose of /api/v1/transactions/198 ('Premium API Access') is not described anywhere
- —No request or response schema is documented; callers must discover behavior empirically
- —The platform lists many endpoint categories but none have documented schemas or example responses
Citations
- —All endpoints priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —Endpoint is live, returns 402 with x402 challenge, maxAmountRequired 20000 USDC base units on Basehttps://lowpaymentfee.com/api/v1/transactions/198
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/transactions/198
- —Platform categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com