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 variety of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. 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/transactions/216` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
The broader platform advertises endpoints for sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and data generation — all at the same $0.02 price point. However, documentation is extremely sparse: the /docs, /api, /pricing, 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 content. The actual functionality behind this specific `/transactions/216` endpoint is unclear beyond its generic "Premium API Access" label.
Capabilities
Use cases
- —Accessing pay-per-call API services without needing API keys or subscriptions
- —Making micropayment-gated API calls settled on Base L2 in USDC
- —Agent-driven workflows that need on-demand API access with crypto payment
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that can handle x402 payment flows autonomously
- —Users who prefer crypto-native micropayments over traditional billing
Not for
- —Users needing detailed API documentation or OpenAPI specs before integrating
- —High-volume use cases where per-request pricing may be less economical than bulk plans
- —Developers who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/216 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming pricing and payment details. However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the actual functionality of this specific endpoint ('Premium API Access' at /transactions/216) is entirely undocumented. The listing is effectively a stub.
Warnings
- —No OpenAPI or schema documentation available — the /docs, /pricing, /api, and /README pages all show only 'Connect wallet' with no content.
- —The actual functionality behind /api/v1/transactions/216 ('Premium API Access') is not described anywhere in the crawled material.
- —The broader platform lists many endpoint categories (AI, finance, analytics, etc.) but none have documented request/response formats.
- —Cannot verify what data or service this specific endpoint actually provides.
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base network.https://lowpaymentfee.com
- —The x402 challenge for /api/v1/transactions/216 requests maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base.https://lowpaymentfee.com/api/v1/transactions/216
- —Platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categories.https://lowpaymentfee.com
- —Documentation pages (/docs, /api, /pricing, /README) render only a 'Connect wallet' prompt with no technical content.https://lowpaymentfee.com/docs