Pay-per-call API platform on Base via x402 — $0.02/request, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad catalog of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and utility services. All endpoints are paid per-request using USDC on the Base network via the x402 protocol, eliminating the need for API keys, subscriptions, or rate limits.
The specific endpoint at `/api/v1/charges/98` is listed as "Premium API Access" and accepts POST requests. The x402 challenge indicates a maximum cost of 20,000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 per request (USDC uses 6 decimals). Payment is sent 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 data generation — all at the same $0.02/request price point. However, documentation 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 content. The actual functionality behind this specific `/charges/98` endpoint and the other listed endpoints cannot be verified from the available material.
Capabilities
Use cases
- —Agents needing on-demand API access without pre-registration or API keys
- —Programmatic access to utility, analytics, or AI endpoints with crypto micropayments
- —Testing x402 protocol integrations on Base network
Fit
Best for
- —Developers wanting zero-signup, pay-as-you-go API access
- —AI agents with USDC on Base that need ad-hoc endpoint calls
- —Projects exploring x402 protocol-based commerce
Not for
- —Users who need detailed API documentation or guaranteed SLAs before purchasing
- —High-volume consumers who want bulk pricing or subscription discounts
- —Anyone without a Base-network USDC wallet
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/98 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge captured) and pricing is clear ($0.02 USDC on Base), but there is zero documentation on what the endpoint actually does, no request/response schemas, no examples, and no OpenAPI spec. The docs/pricing/README pages are all empty beyond a wallet-connect prompt. The listing title 'Premium API Access' is generic and uninformative.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content
- —No OpenAPI or schema definition for any endpoint
- —The specific purpose of /api/v1/charges/98 ('Premium API Access') is completely undocumented
- —Cannot verify what data or functionality any of the advertised endpoints actually return
- —The broad catalog of endpoints (AI, finance, analytics, utils) is listed on the homepage but none have verifiable documentation
Citations
- —The endpoint returns a 402 x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/charges/98
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The platform lists endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com
- —Docs, API, pricing, and README pages render only 'Connect wallet' with no additional contenthttps://lowpaymentfee.com/docs