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/ML inference, finance/Web3, and infrastructure utilities. All endpoints are priced at $0.02 per request, payable in USDC on the Base network with no API keys, no rate limits, and no commitments required. The x402 protocol handles payment inline: callers attach a payment header to each request and receive the response immediately.
The specific endpoint at `/api/v1/charges/195` is listed as "Premium API Access" and returns a 402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. The payment scheme is "exact" with a 300-second timeout. The endpoint accepts POST requests and returns application/json.
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 essentially empty (all sub-pages just show "Connect wallet"), so the actual request/response schemas for individual endpoints are unknown. Without OpenAPI specs or usage examples, callers will need to experiment to discover input parameters and output formats.
Capabilities
Use cases
- —Agents that need on-demand AI inference (sentiment, summarization, classification) without managing API keys
- —Fetching real-time crypto token quotes or gas estimates with per-call payment
- —Geocoding or data validation as a utility service in automated pipelines
- —Exporting analytics data or generating insights reports on demand
Fit
Best for
- —AI agents needing keyless, pay-as-you-go API access
- —Developers who want to avoid subscription commitments for low-volume usage
- —x402-compatible wallets and agent frameworks on Base network
Not for
- —High-volume production workloads where $0.02/request adds up significantly
- —Users who need detailed API documentation and guaranteed SLAs before integrating
- —Callers not set up for x402 / USDC payments on Base
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/charges/195 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-header>" \
-d '{}'Endpoint
Quality
The endpoint is live and returns a valid x402 challenge, and the landing page describes the platform's offerings and pricing. However, there is no OpenAPI spec, no documentation, no request/response schemas, and no usage examples — all doc pages are empty. The specific purpose of '/api/v1/charges/195' beyond 'Premium API Access' is unclear.
Warnings
- —No API documentation available — all doc/pricing/README pages return only 'Connect wallet'
- —No OpenAPI or schema definitions for any endpoint
- —The specific functionality of /api/v1/charges/195 ('Premium API Access') is not described anywhere
- —Request and response formats are completely unknown — callers must guess or experiment
Citations
- —All endpoints priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge requests maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/charges/195
- —Platform offers endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com