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 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 at a flat rate of $0.02 per call, with no API keys, no rate limits, and no minimum commitments required.
The specific endpoint at `/api/v1/transactions/165` is listed as "Premium API Access" and returns an x402 challenge requesting up to 20,000 base units of USDC (0x8335…2913 on Base), which equals $0.02 given USDC's 6 decimals. Payment is made via the x402 exact scheme, settling 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 price point. However, documentation pages (/docs, /pricing, /api, /README) all returned only a "Connect wallet" prompt with no substantive content, so the actual behavior, request schemas, and response formats of these endpoints remain undocumented and unverifiable from the crawl material alone.
Capabilities
Use cases
- —Accessing AI inference endpoints (sentiment, summarization, classification, embeddings) without API key management
- —Fetching real-time crypto token quotes and gas estimates on a per-call basis
- —Running geocoding or data validation utilities with instant USDC micropayments
- —Exporting analytics data or generating reports via pay-as-you-go endpoints
Fit
Best for
- —Developers wanting zero-signup, pay-per-use API access via crypto
- —Agents or bots that need programmatic access to diverse utility endpoints settled on Base
- —Projects already holding USDC on Base looking for frictionless API consumption
Not for
- —Users who need detailed API documentation and response schemas before integrating
- —High-volume consumers who need bulk pricing or subscription discounts
- —Teams that require fiat-only payment rails
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/transactions/165 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-token>" \
-d '{}'Example
Request
{
"url": "https://lowpaymentfee.com/api/v1/transactions/165",
"body": {},
"method": "POST",
"headers": {
"X-PAYMENT": "<x402-payment-token>",
"Content-Type": "application/json"
}
}Endpoint
Quality
The x402 challenge is live and pricing is clear ($0.02 USDC on Base), but all documentation pages returned only 'Connect wallet' with no actual content. There is no OpenAPI spec, no request/response schema, and no examples of what the endpoint actually returns. The endpoint path '/api/v1/transactions/165' with description 'Premium API Access' is vague and doesn't clarify its function.
Warnings
- —All documentation pages (/docs, /pricing, /api, /README) returned only 'Connect wallet' — no substantive documentation available
- —No OpenAPI or schema definition found; request and response formats are unknown
- —The specific endpoint /api/v1/transactions/165 purpose is unclear — 'Premium API Access' is a generic label
- —Cannot verify that the advertised AI, finance, analytics, and utility endpoints actually function as described
Citations
- —Flat pricing of $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —x402 challenge returns maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913) on Basehttps://lowpaymentfee.com/api/v1/transactions/165
- —Platform advertises endpoints for analytics, AI/ML, finance/Web3, and infrastructure utilitieshttps://lowpaymentfee.com