Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
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/transactions/108` is labeled "Premium API Access" and charges up to 20,000 base units of USDC (i.e., $0.02) per call. The platform advertises no API keys, no rate limits, and instant access — you simply attach an x402 payment header to each request.
The broader platform lists 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.
However, documentation is extremely thin. The docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further technical detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The specific functionality behind the `/api/v1/transactions/108` endpoint (labeled generically as "Premium API Access") is unclear — it does not map to any of the named API categories on the landing page. The endpoint is live and returns a valid x402 402 challenge, but without documentation it is difficult to know what data or service it actually provides.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven API consumption without pre-registration or API keys
- —Programmatic pay-as-you-go access to analytics, AI, finance, or utility endpoints
Fit
Best for
- —Developers wanting zero-signup, pay-per-call API access
- —AI agents that can settle x402 payments autonomously
- —Users comfortable paying in USDC on the Base L2 network
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —Anyone requiring free-tier or fiat-only payment options
- —Production workloads that need SLA guarantees or support
Quick start
# The endpoint returns HTTP 402 with an x402 challenge.
# Attach a valid X-PAYMENT header (x402 v1, USDC on Base) to complete the call.
curl -X POST https://lowpaymentfee.com/api/v1/transactions/108 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The endpoint is live and returns a valid x402 402 challenge, confirming it accepts USDC on Base at $0.02/request. However, there is no OpenAPI spec, no request/response schema, no documentation beyond a wallet-connect prompt, and the specific purpose of the /transactions/108 endpoint is undocumented. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available — all docs/pricing/README pages render only 'Connect wallet'
- —The specific endpoint /api/v1/transactions/108 ('Premium API Access') does not correspond to any named API on the landing page; its actual functionality is unknown
- —No example request or response payloads are available anywhere in the crawled material
- —No robots.txt or agents.txt found
Citations
- —The endpoint returns a 402 challenge requesting up to 20,000 base units of USDC (asset 0x8335…) on Base networkhttps://lowpaymentfee.com/api/v1/transactions/108
- —All listed endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —The platform lists APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages all show only a 'Connect wallet' prompthttps://lowpaymentfee.com/docs