Pay-per-call API platform on Base network via x402 — $0.02/request in USDC, no API keys required.
What it does
lowpaymentfee.com is an x402-enabled API marketplace offering a broad set of endpoints across data analytics, AI/ML inference, finance/Web3 data, and utility services. Every endpoint costs $0.02 per request, paid in USDC on the Base network using the x402 payment protocol. There are no API keys, no rate limits, and no sign-up — callers simply attach an x402 payment header to each request.
The specific endpoint at `/api/v1/item/14` is listed as "Premium API Access" and returns `application/json`. Its x402 challenge advertises a max amount of 20,000 base units of USDC (asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. The endpoint accepts POST requests and is discoverable. The payment is settled 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 price point. However, documentation beyond the landing page is extremely sparse (docs, pricing, and README pages all render only a "Connect wallet" prompt), so the actual request/response schemas for individual endpoints are unknown.
Capabilities
Use cases
- —Agents needing on-demand API access without managing API keys or subscriptions
- —Programmatic access to AI inference (sentiment, summarization, classification, embeddings) at micro-payment granularity
- —Fetching real-time finance data (prices, exchange rates, gas estimates) with per-call USDC payment
- —Utility operations like geocoding, validation, and data conversion without rate limits
Fit
Best for
- —AI agents and bots that can settle x402 payments in USDC on Base
- —Developers who want zero-signup, pay-as-you-go API access
- —Low-volume or bursty workloads where per-request pricing is more economical than subscriptions
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where $0.02/request adds up and bulk pricing would be preferred
- —Callers who cannot settle USDC payments on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/item/14 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>"Endpoint
Quality
The x402 challenge is live and confirms pricing and payment details, but the endpoint's actual functionality behind the generic 'Premium API Access' label is unknown. Documentation pages are empty (only 'Connect wallet'), no OpenAPI spec exists, and no request/response schemas are available. The listing is effectively a stub with confirmed liveness.
Warnings
- —The specific purpose of /api/v1/item/14 ('Premium API Access') is unclear — it does not map to any named endpoint on the landing page
- —All documentation pages (docs, pricing, README, api) render only 'Connect wallet' with no actual content
- —No OpenAPI spec or request/response schema is available for any endpoint
- —The breadth of advertised capabilities (AI, finance, geocoding, etc.) cannot be verified from available material
Citations
- —Endpoint returns 402 with x402 challenge advertising 20000 base units of USDC on Base networkhttps://lowpaymentfee.com/api/v1/item/14
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/item/14
- —Platform lists endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com