Pay-per-call API suite on Base (USDC) covering data, AI, finance, and utility endpoints at $0.02/request.
What it does
lowpaymentfee.com is an x402-enabled API platform that offers a broad collection of endpoints spanning data & analytics, AI & machine learning, finance & Web3, and infrastructure utilities. Every endpoint is priced at $0.02 per request, settled in USDC on the Base network. There are no API keys, no rate limits, and no upfront commitments — callers simply attach an x402 payment header to each request.
The probed endpoint (`/api/v2/data`) is listed as "Premium API Access" and returns a valid x402 challenge (version 1, scheme "exact") requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02. The platform advertises additional endpoints including 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.
Documentation is extremely thin: the /docs, /pricing, /api, and /README pages all render only a "Connect wallet" prompt with no further content. There is no OpenAPI spec, no request/response schema documentation, and no usage examples available from the crawl. The actual behavior and response format of `/api/v2/data` (and the other endpoints) cannot be confirmed beyond the x402 challenge metadata.
Capabilities
Use cases
- —Agents that need on-demand data or AI inference without managing API keys
- —Fetching real-time crypto prices, gas estimates, or exchange rates with per-call payment
- —Running sentiment analysis or text summarization via a simple paid HTTP call
- —Geocoding or data validation as a utility microservice
Fit
Best for
- —AI agents and bots that can attach x402 payment headers automatically
- —Developers who want zero-signup, pay-as-you-go API access on Base
- —Low-volume or sporadic callers who don't want subscription commitments
Not for
- —Users who need detailed API documentation or guaranteed SLAs before integrating
- —High-volume production workloads where $0.02/request adds up significantly
- —Callers who cannot settle payments in USDC on the Base network
Quick start
curl -X POST https://lowpaymentfee.com/api/v2/data \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but there is no OpenAPI spec, no request/response schema, no documentation beyond a landing page listing, and no examples. The actual functionality of /api/v2/data is unknown — it could be a stub. This is effectively a stub listing.
Warnings
- —No OpenAPI spec or schema documentation available
- —All documentation pages (/docs, /pricing, /api, /README) render only 'Connect wallet' with no content
- —Request and response formats for /api/v2/data are completely undocumented
- —The actual data or functionality returned by this endpoint is unverified
- —The broad range of advertised endpoints (AI, finance, geo, etc.) cannot be independently confirmed as functional
Citations
- —The endpoint returns a valid x402 challenge with maxAmountRequired of 20000 base units of USDC on Basehttps://lowpaymentfee.com/api/v2/data
- —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 advertises endpoints across data & analytics, AI & ML, finance & Web3, and infrastructure categorieshttps://lowpaymentfee.com
- —USDC asset address is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v2/data