Pay-per-call API platform on Base network via x402 — data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/ach/17` is listed as "Premium API Access" and costs up to $0.02 per call (maxAmountRequired of 20,000 base units of USDC, which has 6 decimals = $0.02). No API keys, rate limits, or subscriptions are required — each request is paid individually via an X-PAYMENT header.
The broader platform advertises multiple API 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 listed at the same $0.02/request price point.
However, documentation is extremely sparse. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no actual technical documentation, request/response schemas, or usage examples. The specific functionality behind the `/api/v1/ach/17` endpoint path is unclear — the "ach" segment might suggest ACH (Automated Clearing House) payment-related functionality, but this is not documented anywhere. Without schemas or examples, it is impossible to confirm what this endpoint actually returns or what input it expects beyond a POST request.
Capabilities
Use cases
- —Paying per-request for API access without subscriptions or API keys
- —Integrating x402-compatible agents with pay-as-you-go endpoints
- —Accessing premium data or services via crypto micropayments on Base
Fit
Best for
- —Developers wanting zero-commitment, pay-per-call API access
- —x402-compatible AI agents that can settle payments on Base
- —Users who prefer crypto micropayments over traditional API billing
Not for
- —Anyone needing detailed API documentation or guaranteed SLAs
- —Use cases requiring well-documented request/response schemas
- —High-volume consumers who would benefit from bulk pricing
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/ach/17 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The x402 challenge is live and confirms pricing ($0.02 USDC on Base), but there is zero documentation for this specific endpoint. No request/response schema, no examples, and the docs pages are empty. The purpose of /api/v1/ach/17 is unclear.
Warnings
- —Documentation pages (docs, API, pricing, README) all return only 'Connect wallet' with no actual content
- —No OpenAPI spec or request/response schema available
- —The specific functionality of /api/v1/ach/17 ('Premium API Access') is undocumented — the 'ach' path segment is unexplained
- —No examples of successful responses exist in the crawl material
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/ach/17
- —USDC asset address 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base networkhttps://lowpaymentfee.com/api/v1/ach/17
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Multiple API categories listed: Data & Analytics, AI & ML, Finance & Web3, Infrastructurehttps://lowpaymentfee.com