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 set of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are paid per-request using USDC on the Base network at a flat rate of $0.02 per call, with no API keys, no rate limits, and no commitments required.
The specific endpoint at `/api/v1/transactions/327` is listed as "Premium API Access" and accepts POST requests. The x402 challenge confirms it is live, requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is settled on-chain to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The platform also advertises additional endpoint categories including sentiment analysis, text summarization, classification, embeddings, price feeds, exchange rates, token quotes, gas estimates, geocoding, validation, conversion, and 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, schemas, or example payloads. Without documentation it is unclear what request body this specific transactions endpoint expects or what response format it returns.
Capabilities
Use cases
- —Accessing analytics metrics and reports on a pay-per-use basis without API key management
- —Running AI inference tasks (sentiment, summarization, classification, embeddings) with per-call USDC payments
- —Fetching real-time crypto token quotes, gas estimates, and exchange rates
- —Performing utility operations like geocoding, validation, and data conversion
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access settled in USDC on Base
- —Agents and bots that can handle x402 payment flows natively
- —Users who prefer no rate limits and no API key registration
Not for
- —Users who need detailed API documentation, schemas, or example payloads before integrating
- —Applications requiring non-crypto payment methods or fiat billing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/327 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is confirmed live via a valid 402 challenge with clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation beyond a landing page listing, no request/response examples, and all doc pages render only 'Connect wallet'. The purpose of this specific /transactions/327 endpoint is unclear beyond the generic 'Premium API Access' label.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all return only 'Connect wallet' with no usable content
- —No OpenAPI or schema available — request body and response format for /api/v1/transactions/327 are unknown
- —The endpoint path '/api/v1/transactions/327' with a numeric ID is ambiguous; it is unclear what resource or action this represents
- —No examples or error documentation available
Citations
- —Flat pricing of $0.02 per request across all endpoints, no API keys, no rate limitshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/327
- —Available endpoint categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet'https://lowpaymentfee.com/docs