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 infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no commitments required. The x402 protocol handles payment inline: callers attach a signed USDC payment in the X-PAYMENT header and receive the response immediately.
The specific endpoint at `/api/v1/transactions/244` is listed as "Premium API Access" and returns `application/json` via POST. The x402 challenge confirms it is live, accepting exact-scheme payments of up to 20,000 base units of USDC (0.02 USD) on Base (asset contract 0x8335…2913). The platform 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.
Documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawled material. The exact functionality behind the `/api/v1/transactions/244` path is unclear — the name "Premium API Access" is generic and does not describe a specific capability.
Capabilities
Use cases
- —Programmatic access to various data, AI, and utility endpoints without managing API keys or subscriptions
- —Agent-driven workflows that need to pay per call using on-chain USDC on Base
- —Exploring x402 protocol integration for pay-as-you-go API consumption
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, per-request API access on Base
- —Low-volume or bursty workloads where flat per-call pricing is convenient
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where $0.02/request adds up quickly
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/244 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <signed-x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base). However, there is no OpenAPI spec, no documentation beyond a landing page, no request/response schemas, and the specific purpose of /api/v1/transactions/244 is undefined. The docs/pricing/README pages are all blank wallet-connect stubs.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content
- —The specific functionality of /api/v1/transactions/244 ('Premium API Access') is completely undocumented
- —No OpenAPI spec or request/response schema provided
- —No examples of expected input or output format
- —The broad catalog of endpoints (AI, finance, utils) is advertised but none are documented with schemas or sample payloads
Citations
- —All endpoints cost $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge confirms the endpoint is live, accepting up to 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/244
- —Platform offers endpoints across Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com