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, rate limits, or subscriptions are required — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/transactions/197` is listed as "Premium API Access" and its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02. The platform also advertises endpoints for 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 per call.
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 schema, no request/response examples, and no detailed descriptions of what each endpoint actually returns. The x402 challenge confirms the endpoint is live and accepting POST requests, but without documentation it is unclear what request body this particular endpoint expects or what response it produces.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching financial data like token quotes, exchange rates, and gas estimates on a per-call basis
- —Using utility services like geocoding, validation, and data conversion with instant micropayments
Fit
Best for
- —Agents or developers who want zero-setup, pay-as-you-go API access
- —Use cases requiring no subscriptions, API keys, or rate limits
- —Crypto-native workflows already operating on the Base network
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscription plans
- —Anyone without access to USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/197 \
-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 documentation is effectively nonexistent — every doc page renders only 'Connect wallet'. There is no OpenAPI schema, no request/response examples, and no description of what this specific endpoint does beyond 'Premium API Access'. The endpoint's actual functionality cannot be verified.
Warnings
- —Documentation pages (/docs, /api, /pricing, /README) all render only 'Connect wallet' with no usable content
- —No OpenAPI or schema available — request body and response format for /api/v1/transactions/197 are unknown
- —The endpoint path '/api/v1/transactions/197' with description 'Premium API Access' does not match any of the advertised API categories on the landing page, making its purpose unclear
- —Cannot verify that any of the advertised AI, finance, or utility endpoints actually function as described
Citations
- —All endpoints priced at $0.02 per request with no API keys, rate limits, or minimumshttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/transactions/197
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/197
- —Platform advertises endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com