Check ETH wallet balances via x402 micropayment on Base for $0.02 per request.
What it does
This endpoint at lowpaymentfee.com returns ETH wallet balance data, accessible through the x402 payment protocol. It is part of a broader suite of pay-per-call APIs offered by the same provider, spanning data analytics, AI/ML inference, finance/Web3, and utility services. All endpoints on the platform share a uniform $0.02 per-request pricing model, settled in USDC on the Base network.
The specific endpoint `/api/v1/wallet/ETH/balance` accepts POST requests and returns JSON. Payment is handled via the x402 exact-payment scheme: callers attach an `X-PAYMENT` header with a signed USDC payment of up to 20,000 base units (i.e., $0.02, since USDC uses 6 decimals). The payment is directed to address `0x1A2B13E97f5F837C8F9FA1F95a1484B7C70d85F3` on Base, using the USDC contract `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`. No API keys or rate limits are advertised; access is instant once payment is provided.
Documentation is extremely sparse. The provider's docs, API, pricing, 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. The endpoint is confirmed live (returns a proper 402 challenge), but the actual request body format and response structure are unknown.
Capabilities
Use cases
- —Querying ETH wallet balances programmatically without managing API keys
- —Integrating wallet balance checks into agent workflows that support x402 payments
- —Building dashboards or bots that need on-demand ETH balance data
Fit
Best for
- —Agents or apps that already support x402 payment flows on Base
- —Low-volume, on-demand ETH balance lookups without subscription commitments
- —Developers who want keyless API access paid per call in USDC
Not for
- —High-volume balance monitoring where per-request fees add up quickly
- —Users who need detailed transaction history or token balances beyond ETH
- —Anyone requiring well-documented request/response schemas before integration
Quick start
curl -X POST https://lowpaymentfee.com/api/v1/wallet/ETH/balance \
-H "Content-Type: application/json" \
-H "X-PAYMENT: <x402-signed-payment-header>" \
-d '{"address": "0xYourEthAddress"}'Example
Request
{
"address": "0x1234567890abcdef1234567890abcdef12345678"
}Endpoint
Quality
The endpoint is confirmed live with a valid x402 402 challenge, and pricing is clear ($0.02/request in USDC on Base). However, there is no documentation, no OpenAPI spec, no request/response schema, and no examples. The request body format and response structure are entirely unknown and had to be guessed. This is effectively a stub listing.
Warnings
- —No documentation available — docs, API, pricing, and README pages all show only 'Connect wallet' with no content.
- —Request body schema is unknown; the example_request_json is speculative.
- —Response schema is completely undocumented; example_response_json is null.
- —No OpenAPI or machine-readable spec provided by the endpoint.
- —The provider offers many endpoints but none appear to have public documentation.
Citations
- —The endpoint returns a 402 challenge with x402Version 1, exact scheme, on Base network, with maxAmountRequired of 20000 base units of USDChttps://lowpaymentfee.com/api/v1/wallet/ETH/balance
- —USDC asset contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Basehttps://lowpaymentfee.com/api/v1/wallet/ETH/balance
- —All APIs on the platform are priced at $0.02 per request with no API keys, no rate limits, and instant access on Base networkhttps://lowpaymentfee.com
- —The provider offers endpoints across Data & Analytics, AI & ML, Finance & Web3, and Infrastructure categorieshttps://lowpaymentfee.com