Track USDC Whale

WHAT IT DOES

This tool monitors USDC whale wallet addresses for balance changes and transfer activity. You provide a whale wallet address and the USDC token contract address for your network, and the tool tracks the whale's USDC balance using ERC-20 balanceOf and scans for Transfer events using eth_getLogs with chunked scanning. When the whale's USDC balance changes by more than a minimal threshold, or when a Transfer event is detected, the tool logs the activity and displays a visual alert. All tracking configurations are stored in-memory — no data is persisted across page reloads.

HOW TO USE

Connect your MetaMask wallet using the Connect button. The USDC contract address is pre-filled for Ethereum mainnet — you can change it for other networks. Enter the whale wallet address you want to track, give it a name/label, and choose a check interval (5-300 seconds). Click "Track Whale" to start monitoring. Active tracked whales appear in the list with their current USDC balance. When the whale's balance changes or a transfer is detected, the activity appears in the USDC Whale Activity log with a timestamp. Click any transaction hash to view it on Etherscan. Use "Untrack" to stop monitoring a whale or "Clear All" to remove all tracked whales and activity history.

TECHNICAL MECHANISM

The tool uses the BGWallet bridge to access the blockchain provider via ethers.js. For each tracked whale, it creates a JavaScript interval that runs at the user-specified frequency. On each interval tick, it fetches the whale's USDC balance using the ERC-20 balanceOf view function, formatted with the token's decimals (default 6 for USDC). It compares the new balance against the previously stored balance and logs any change above 0.01 USDC. It also scans for Transfer events using eth_getLogs with the USDC contract address as the filter. To handle varying RPC limits, the tool implements a chunked scanning strategy — it starts with a chunk size of 500 blocks and halves the chunk size if the RPC returns a "limit exceeded" error, continuing until the scan completes. Deduplication is handled using a Set of seen event keys (transaction hash + log index).

WHAT IT CANNOT SEE

This tool cannot persist tracking across page reloads because it runs in an opaque-origin sandboxed frame with no storage access. It cannot send push notifications or emails without external services. It cannot detect activity that occurred before the whale was added to tracking. It cannot monitor wallets other than those specified. It cannot detect pending or failed transactions — only confirmed transactions. It cannot detect USDC transfers on networks other than the connected network. It cannot detect transactions sent from the whale wallet to itself. It cannot verify that the tracked address is actually a "whale" (large holder). It cannot detect USDC transfers via non-standard ERC-20 implementations. It cannot detect USDC approvals or other events.

PLEASE NOTE

This tool works only with EVM-compatible wallets connected via the BGWallet bridge. The default USDC address is for Ethereum mainnet — you must update it for other networks (Polygon: 0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174, Arbitrum: 0xaf88d065e77c8cC2239327C5EDb3A432268e5831, etc.). The chunked scanning ensures compatibility with RPC providers that limit eth_getLogs ranges, but scanning large ranges may take time. Frequent polling may hit RPC rate limits on public providers. Tracking is in-memory only and will be lost when the page is refreshed or closed. The tool does not store or transmit any data — all processing occurs in your browser. This tool is provided as a lightweight USDC whale tracking utility and should not be used as a critical financial monitoring system.