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 variety of endpoints across data & analytics, AI & machine learning, finance & Web3, and infrastructure utility categories. All endpoints are paid per-request using USDC on the Base network, with no API keys, no rate limits, and no minimum commitments required.
The specific endpoint at `/api/v1/charges/377` is listed as "Premium API Access" and accepts POST requests. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 per request (USDC uses 6 decimals). Payment is made via the x402 exact scheme, settling to address 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3 with a 300-second timeout.
The broader platform advertises endpoints for 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/request price point. However, 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 request/response schema documentation, and no usage examples available from the crawled material.
Capabilities
Use cases
- —Accessing premium API functionality with per-call USDC micropayments
- —Agent-driven workflows that need keyless, pay-as-you-go API access
- —Integrating x402-compatible endpoints into crypto-native applications
Fit
Best for
- —Developers wanting zero-commitment, pay-per-use API access
- —AI agents with x402 payment capability on Base
- —Users who prefer crypto micropayments over subscription billing
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Developers without USDC on Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/377 \
-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 OpenAPI spec, no documented request/response schema, no examples, and all documentation pages beyond the landing page are empty ('Connect wallet' only). The purpose of this specific '/charges/377' endpoint is unclear beyond the generic 'Premium API Access' label.
Warnings
- —No OpenAPI or schema documentation available — request and response formats are unknown
- —All documentation pages (/docs, /api, /pricing, /README) render only 'Connect wallet' with no content
- —The specific functionality of /api/v1/charges/377 ('Premium API Access') is not described anywhere
- —Cannot verify what data or service this endpoint actually returns
Citations
- —All endpoints priced at $0.02/request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/charges/377
- —Platform offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com