Pay-per-call API platform on Base (USDC) offering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that provides a broad collection of endpoints spanning data analytics, AI/ML inference, finance/Web3 data, and general utility services. All endpoints are paid per-request using USDC on the Base network via the x402 protocol — no API keys, no rate limits, and no subscriptions required.
The specific endpoint at `/api/v1/keys/60` is listed as "Premium API Access" and costs up to $0.02 per call (maxAmountRequired of 20,000 base units of USDC with 6 decimals). The platform advertises a uniform $0.02/request pricing across all its endpoints. Categories of available APIs include: metrics and reports (Data & Analytics), sentiment analysis, text summarization, classification, and embeddings (AI & ML), price feeds, exchange rates, token quotes, and gas estimates (Finance & Web3), and geocoding, validation, conversion, and generation (Infrastructure/Utilities).
Payment is settled on-chain via USDC (contract 0x8335…2913) on Base to address 0x1A2B…85F3. The x402 challenge was successfully captured with version 1, confirming the endpoint is live. No OpenAPI schema, detailed documentation, or example request/response payloads were found in the crawl — the /api, /pricing, and /README pages all returned only a "Connect wallet" prompt with no substantive content.
Capabilities
Use cases
- —Agents needing on-demand AI inference (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto gas estimates, token quotes, or exchange rates with per-call payment
- —Running data analytics or generating reports with no subscription commitment
- —Geocoding, data validation, or format conversion as utility microservices
Fit
Best for
- —AI agents that can settle x402 payments in USDC on Base
- —Developers wanting zero-commitment, pay-as-you-go API access
- —Use cases requiring low-cost ($0.02) individual API calls without rate limits
Not for
- —Users who need detailed API documentation or OpenAPI specs before integrating
- —High-volume consumers who would benefit from bulk/subscription pricing
- —Anyone unable to pay with USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/keys/60 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02/request in USDC on Base). However, there is no OpenAPI schema, no request/response examples, and no meaningful documentation — the /api, /pricing, and /README pages are all blank beyond a wallet-connect prompt. The purpose of the specific /api/v1/keys/60 'Premium API Access' endpoint is unclear relative to the other listed endpoints.
Warnings
- —No OpenAPI or schema documentation available for any endpoint
- —The /api, /pricing, and /README pages returned no useful content (only 'Connect wallet')
- —The specific function of /api/v1/keys/60 ('Premium API Access') is not documented — it may be a key-generation or meta endpoint rather than a data endpoint
- —No example request or response payloads are available anywhere in the crawl
Citations
- —Uniform pricing of $0.02 per request across all endpointshttps://lowpaymentfee.com
- —maxAmountRequired is 20000 base units of USDC (6 decimals) = $0.02https://lowpaymentfee.com/api/v1/keys/60
- —Payment settled in USDC on Base network to 0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3https://lowpaymentfee.com/api/v1/keys/60
- —Available API categories include Data & Analytics, AI & ML, Finance & Web3, and Infrastructurehttps://lowpaymentfee.com
- —No API keys, no rate limits, instant access advertisedhttps://lowpaymentfee.com