Pay-per-call API platform on Base network via x402 — $0.02/request in USDC.
What it does
lowpaymentfee.com is a pay-per-request API platform that uses the x402 protocol to accept USDC payments on the Base network. The specific endpoint `/api/v1/wire/91` is listed as "Premium API Access" and returns a standard x402 402 challenge requesting up to 20,000 base units of USDC (i.e., $0.02 given USDC's 6 decimals) per call. No API keys or rate limits are required — callers simply attach an X-PAYMENT header with a valid x402 payment proof.
The broader platform advertises multiple API categories including Data & Analytics (metrics, reports, data export, insights), AI & Machine Learning (sentiment analysis, text summarization, classification, embeddings), Finance & Web3 (price feeds, exchange rates, token quotes, gas estimates), and Infrastructure utilities (geocoding, validation, conversion, generation). All endpoints are uniformly priced at $0.02 per request. However, the specific functionality behind `/api/v1/wire/91` is not documented beyond the label "Premium API Access," so its exact behavior and response format are unclear.
Payments settle on the Base L2 network to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` using the USDC contract at `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`. The endpoint accepts POST requests and returns `application/json`. Documentation pages (docs, pricing, README) all rendered only a "Connect wallet" prompt with no additional technical detail.
Capabilities
Use cases
- —Programmatic access to a premium API endpoint with per-call USDC micropayments
- —Agent-driven workflows that need keyless, pay-as-you-go API access on Base
- —Integrating x402-compatible payment flows into automated pipelines
Fit
Best for
- —Developers or agents already holding USDC on Base who want frictionless API access
- —x402-native agent toolchains that auto-negotiate payment challenges
- —Low-volume, on-demand API consumption without subscription commitments
Not for
- —Users who need detailed documentation or well-defined response schemas before integrating
- —High-volume consumers who would benefit from bulk pricing or subscriptions
- —Anyone without a Base-compatible wallet or USDC holdings
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/wire/91 \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-payment-proof>" \
-d '{}'Endpoint
Quality
The endpoint is live (402 challenge confirmed) and pricing is clear ($0.02 USDC on Base), but there is no documentation of what /api/v1/wire/91 actually does, no request/response schema, and all doc pages render only 'Connect wallet'. The specific functionality behind 'Premium API Access' is entirely opaque.
Warnings
- —The exact functionality of /api/v1/wire/91 is undocumented — 'Premium API Access' is the only description available.
- —All documentation pages (/docs, /pricing, /README, /api) returned only a 'Connect wallet' prompt with no technical content.
- —No OpenAPI spec, request schema, or response schema is available for this endpoint.
- —The broader site lists many API categories but it is unclear which, if any, map to this specific wire/91 endpoint.
Citations
- —The endpoint returns a 402 x402 challenge requesting up to 20,000 base units of USDC on Basehttps://lowpaymentfee.com/api/v1/wire/91
- —USDC contract address on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/wire/91
- —All endpoints are priced at $0.02 per request with no API keys, no rate limits, and instant accesshttps://lowpaymentfee.com
- —Platform offers Data & Analytics, AI & ML, Finance & Web3, and Infrastructure API categorieshttps://lowpaymentfee.com