Check account balance via x402 micropayment on Base network for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com provides account balance information behind an x402 paywall. It is part of a broader platform offering various API categories including data analytics, AI/ML inference, finance/Web3, and infrastructure utilities—all priced at $0.02 per request settled in USDC on the Base network.
The specific endpoint `/api/v1/accounts/185/balance` accepts POST requests and returns JSON. Payment is handled via the x402 protocol: callers must include an X-PAYMENT header with a valid payment proof. The challenge advertises a maxAmountRequired of 20000 base units of USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base), which equals $0.02 given USDC's 6 decimals. No API keys or rate limits are required—access is purely pay-per-call.
Documentation on the site is extremely sparse; the docs, API, pricing, and README pages all render only a "Connect wallet" prompt with no additional technical detail. There is no OpenAPI spec, no request/response schema documentation, and no example payloads available. The endpoint is confirmed live (returns 402 challenge correctly), but the actual response format after successful payment is unknown.
Capabilities
Use cases
- —Querying account balance information programmatically with per-call payment
- —Integrating balance checks into agent workflows without pre-registration
- —Demonstrating x402 protocol micropayment flows
Fit
Best for
- —Agents needing on-demand account balance data without API key setup
- —Developers experimenting with x402 pay-per-call patterns
- —Low-volume balance queries where subscription pricing is unnecessary
Not for
- —High-volume balance polling where per-call costs accumulate quickly
- —Users who need detailed documentation or guaranteed SLAs
- —Applications requiring authenticated multi-account management
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/accounts/185/balance \
-H "X-PAYMENT: <x402_payment_proof>" \
-H "Content-Type: application/json"Endpoint
Quality
The endpoint is confirmed live with a valid 402 challenge, but there is no documentation, no OpenAPI spec, no request/response examples, and the docs pages are empty. The purpose of the specific endpoint (account 185 balance) is unclear and undocumented.
Warnings
- —No OpenAPI or schema documentation available
- —All documentation pages render only 'Connect wallet' with no content
- —No request body schema or response format documented
- —Purpose of 'account 185' is unexplained—may be a demo or placeholder
- —Platform appears to be a generic x402 demo site with many listed endpoints but no substantive docs
Citations
- —Endpoint returns 402 with x402 challenge advertising USDC on Base at maxAmountRequired 20000 (=$0.02)https://lowpaymentfee.com/api/v1/accounts/185/balance
- —Platform advertises $0.02/request pricing with no API keys, no rate limits, instant access on Base networkhttps://lowpaymentfee.com
- —USDC contract on Base is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913https://lowpaymentfee.com/api/v1/accounts/185/balance