Pay-per-call premium API access on Base via x402 protocol at $0.02/request in USDC.
What it does
lowpaymentfee.com offers a suite of pay-per-request APIs accessible via the x402 payment protocol on the Base network. The specific endpoint `/api/v1/transactions/101` is labeled "Premium API Access" and requires a payment of up to 20,000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913), which equals $0.02 per request (USDC uses 6 decimals). No API keys, rate limits, or subscriptions are needed—callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises 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 listed at the same $0.02/request price point and settle on Base using USDC.
Documentation beyond the landing page is extremely sparse—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 example request/response payloads, and no description of what the `/api/v1/transactions/101` endpoint actually returns. The endpoint is confirmed live (returns a proper 402 x402 challenge), but the lack of documentation makes it difficult to determine the actual functionality behind this specific route.
Capabilities
Use cases
- —Programmatic access to premium data or services without subscription commitments
- —Agent-driven workflows that need instant API access without credential provisioning
- —Demonstrating x402 payment protocol integration on Base
Fit
Best for
- —Developers experimenting with x402 payment flows
- —AI agents needing credential-free API access
- —Low-volume or sporadic API consumers who prefer pay-per-use
Not for
- —Users needing detailed API documentation or guaranteed SLAs
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-compatible USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/101 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_proof>"Endpoint
Quality
The endpoint is confirmed live with a valid 402 x402 challenge, and the landing page provides basic pricing and category info. However, there is no OpenAPI spec, no documentation, no example requests/responses, and the specific functionality of /api/v1/transactions/101 is entirely undocumented. This is effectively a stub listing.
Warnings
- —No OpenAPI or schema documentation available
- —The /docs, /pricing, /api, and /README pages are all empty (only show 'Connect wallet')
- —The specific functionality of /api/v1/transactions/101 is undocumented—unclear what data it returns
- —No example request or response payloads available anywhere in crawled content
Citations
- —Endpoint returns 402 with x402 challenge requiring up to 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transactions/101
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/transactions/101
- —All endpoints priced at $0.02/request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —Platform offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com