Pay-per-call premium API access on Base via x402 — $0.02 per request in USDC.
What it does
This endpoint at lowpaymentfee.com provides "Premium API Access" via the x402 payment protocol. The site hosts a broad catalog of pay-per-call APIs spanning data & analytics, AI/ML inference (sentiment analysis, 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, settled in USDC on the Base network.
The specific endpoint `/api/v1/charges/360` is labeled "Premium API Access" in the x402 challenge. The challenge advertises a maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, which has 6 decimals), equating to $0.02 per call. Payment is made via the x402 exact scheme with no API keys or rate limits required — callers simply attach an X-PAYMENT header. The endpoint accepts POST requests and returns application/json.
Documentation is extremely sparse: the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema, and no examples available. It is unclear what specific functionality the `/api/v1/charges/360` path provides versus the other listed endpoints. The site appears to be a demonstration or early-stage platform for x402-gated APIs.
Capabilities
Use cases
- —Accessing pay-per-call API services without subscription or API key management
- —Making micropayments in USDC on Base for on-demand API calls
- —Integrating x402-compatible agents with utility and data endpoints
Fit
Best for
- —Developers wanting zero-commitment, pay-as-you-go API access
- —AI agents that support x402 payment protocol on Base
- —Projects needing low-cost per-request pricing without rate limits
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume use cases where subscription pricing would be more economical
- —Developers who cannot transact in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/360 \
-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 payments. However, there is no documentation, no request/response schema, no examples, and the specific functionality of /api/v1/charges/360 is unclear. The docs pages are empty beyond a wallet connect prompt. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or request/response schema available
- —All documentation pages (docs, API, pricing, README) render only 'Connect wallet' with no content
- —The specific functionality of /api/v1/charges/360 ('Premium API Access') is not documented — it is unclear what data or service it returns
- —The site may be a demo or early-stage platform; reliability and uptime are unknown
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Base networkhttps://lowpaymentfee.com/api/v1/charges/360
- —Site offers APIs across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com