Pay-per-call API platform on Base via x402 — data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of pay-per-request endpoints across four categories: Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are priced at $0.02 per request, paid in USDC on the Base network.
The specific endpoint at `/api/v1/wire/111` is listed as "Premium API Access" and returns a valid x402 challenge requesting up to 20,000 base units of USDC (0.02 USDC, i.e., $0.02) on Base. Payment is made via the x402 exact scheme with no API keys or rate limits required — callers simply attach an X-PAYMENT header to each POST request. The payment address is `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` and the timeout is 300 seconds.
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 examples of what any endpoint actually returns. The landing page lists endpoints and prices but provides no detail on input parameters or output formats. The exact purpose of the `/api/v1/wire/111` endpoint versus the other listed endpoints is unclear.
Capabilities
Use cases
- —Accessing AI inference (sentiment, summarization, classification, embeddings) without API key signup
- —Fetching real-time financial data like token quotes, exchange rates, and gas estimates via micropayment
- —Running utility operations like geocoding, validation, and data conversion on a per-call basis
- —Integrating pay-per-use data analytics and export into agent workflows
Fit
Best for
- —AI agents needing low-friction, keyless API access to common utilities
- —Developers who want to avoid subscription commitments for infrequent API calls
- —Web3-native applications that can pay in USDC on Base
Not for
- —High-volume production workloads where $0.02/request adds up significantly
- —Users who need detailed API documentation, SLAs, or guaranteed uptime
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/wire/111 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, and the landing page lists available endpoints with pricing. However, there is no OpenAPI spec, no documentation beyond the landing page, no request/response examples, and the specific purpose of /api/v1/wire/111 is undocumented. Most details must be inferred.
Warnings
- —No OpenAPI spec or schema documentation available
- —Docs, API, pricing, and README pages all render only 'Connect wallet' with no content
- —The specific purpose and input/output format of /api/v1/wire/111 is unclear — it may be a generic or demo endpoint
- —No information on uptime, SLAs, or rate limits beyond the claim of 'no rate limits'
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0.02 USD) on Basehttps://lowpaymentfee.com/api/v1/wire/111
- —Available categories include Data & Analytics, AI & Machine Learning, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —Docs, pricing, API, and README pages show only 'Connect wallet'https://lowpaymentfee.com/docs