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 at `/api/v1/charges/162` is labeled "Premium API Access" and accepts POST requests, returning JSON responses. Payment is settled on-chain to a specified wallet address using USDC (contract 0x8335…2913 on Base), with a maximum charge of 20,000 base units (i.e., $0.02 given USDC's 6 decimals).
The broader platform advertises multiple API categories including 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 $0.02 per request. The platform emphasizes no API keys, no rate limits, no minimums, and instant access.
However, the specific endpoint `/api/v1/charges/162` does not clearly map to any of the listed API categories — it sits under a `/charges/` path that isn't documented on the site. There is no OpenAPI schema, no detailed documentation (the /docs, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content), and no example request/response payloads are available. The endpoint is confirmed live via a valid 402 challenge, but what it actually returns upon successful payment is unknown.
Capabilities
Use cases
- —Accessing premium API data with per-request USDC micropayments on Base
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Testing x402 protocol integrations with low-cost endpoints
Fit
Best for
- —Developers experimenting with x402 payment protocol
- —Agents needing keyless API access with crypto micropayments
- —Users who want per-call pricing without subscriptions or rate limits
Not for
- —Users who need detailed API documentation or schemas before integrating
- —Anyone without a Base-network USDC wallet
- —High-volume use cases where $0.02/request adds up quickly without bulk discounts
Quick start
# The endpoint requires an X-PAYMENT header with a valid x402 payment proof.
# Using curl (you need an x402-compatible client to generate the header):
curl -X POST https://lowpaymentfee.com/api/v1/charges/162 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402_payment_token>"Endpoint
Quality
The endpoint is confirmed live with a valid 402 challenge and clear pricing ($0.02 USDC on Base). However, there is no OpenAPI schema, no documentation beyond a landing page listing, no example requests or responses, and the specific /charges/162 path is not explained anywhere. The docs/pricing/README pages are all empty. This is effectively a stub listing.
Warnings
- —The /charges/162 path does not correspond to any documented API endpoint on the site
- —No OpenAPI schema or detailed documentation available — /docs, /pricing, and /README pages are empty
- —No example request or response payloads are available; what the endpoint returns upon payment is unknown
- —The platform lists many API categories but provides no technical details for any of them
Citations
- —The endpoint returns a 402 challenge requesting USDC payment on Base network with maxAmountRequired of 20000 base unitshttps://lowpaymentfee.com/api/v1/charges/162
- —USDC asset contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/charges/162
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform lists Data & Analytics, AI & ML, Finance & Web3, and Infrastructure API categorieshttps://lowpaymentfee.com
- —Docs, pricing, and README pages contain only a 'Connect wallet' prompt with no substantive contenthttps://lowpaymentfee.com/docs