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 broad set of endpoints across data analytics, AI/ML inference, finance/Web3, and infrastructure utilities. Every endpoint costs $0.02 per request, paid in USDC on the Base network with no API keys, no rate limits, and no commitments required. The x402 protocol handles payment inline: callers attach a payment header to each HTTP request, and the server fulfills the call once payment is verified.
The specific endpoint at `/api/v1/transfers/55` is listed as "Premium API Access." Its x402 challenge advertises a maxAmountRequired of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts POST requests and returns application/json. Beyond the generic "Premium API Access" label, no further documentation describes what this particular transfer endpoint returns or what input it expects.
The broader platform advertises categories including metrics, reports, data export, insights, 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 price point. However, documentation pages (/docs, /pricing, /README) returned only a "Connect wallet" prompt with no substantive content, so the actual behavior and schemas of these endpoints remain unverified.
Capabilities
Use cases
- —Agents that need on-demand API access without pre-registration or API keys
- —Programmatic access to utility endpoints (geocoding, validation, conversion) with per-call crypto payment
- —Exploring x402 protocol integration for pay-as-you-go service consumption
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless, pay-per-use API access on Base
- —Low-volume or sporadic API consumers who want no subscription commitment
Not for
- —Production workloads requiring well-documented, schema-validated endpoints
- —Users who need fiat payment rails or cannot transact in USDC on Base
- —High-throughput use cases where $0.02/request adds up significantly
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transfers/55 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>"Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base). However, there is no documentation, no input/output schema, and no description of what /api/v1/transfers/55 actually does. The docs, pricing, and README pages all returned only 'Connect wallet' with no content. This is effectively a stub listing.
Warnings
- —No documentation available — /docs, /pricing, and /README pages all returned only 'Connect wallet' with no substantive content
- —The purpose of /api/v1/transfers/55 ('Premium API Access') is completely undocumented; it is unclear what data or service it provides
- —No input or output schema is available; callers cannot know what request body to send or what response to expect
- —The platform lists many endpoint categories (AI, finance, analytics, etc.) but none are verified to actually function
Citations
- —Endpoint returns 402 with x402 challenge advertising maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/transfers/55
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/transfers/55
- —Documentation pages (/docs, /pricing, /README) returned only 'Connect wallet' with no contenthttps://lowpaymentfee.com/docs