Testnet Contract Address Bookmarking Tool

WHAT IT DOES

This tool connects to your EVM wallet and helps you manage and organize contract addresses across multiple testnet networks. It allows you to bookmark contract addresses with custom names and tags, making it easy to keep track of deployed contracts during development. The tool supports multiple networks including Goerli, Sepolia, Mumbai, BNB Testnet, Arbitrum Goerli, Optimism Goerli, and Base Goerli. Each bookmark stores the contract address, name, network ID, and user-defined tags for easy filtering and organization.

HOW TO USE

Connect your Web3 wallet using the Connect button. Enter a name for the contract, the contract address, and optional tags (comma-separated) in the input fields. Select the network from the dropdown. Click "Add Bookmark" to save the contract. Click "Verify Address" to check if the address has deployed code on the current network. Click "Clear All" to remove all bookmarks. Results appear in the Results card with a summary of total bookmarks and unique networks, followed by a list of all bookmarks with their names, addresses, networks, tags, and delete buttons.

TECHNICAL MECHANISM: IN-MEMORY BOOKMARK STORAGE WITH NETWORK TAGGING

The tool maintains an in-memory array of bookmark objects, each containing name, address, chainId, tags array, and creation timestamp. Bookmarks are stored as a JavaScript array in the page's memory, allowing for fast add, delete, and render operations. The network dropdown provides a selection of testnet chain IDs, and bookmarks are tagged with the selected network. When rendering, the tool groups bookmarks and displays network names using the dropdown options. The verify function uses the connected provider's getCode() method to check if a contract is deployed at the specified address on the current network.

WHAT IT CANNOT SEE

This tool cannot persist bookmarks across page reloads without external storage—all bookmarks are in-memory only and will be lost on refresh. It cannot sync bookmarks between devices or sessions—each session starts with an empty bookmark list. It cannot verify that bookmarked addresses correspond to actual deployed contracts without on-chain queries—verification requires an active connection and RPC support. It relies on user input for address validity and may not detect typos—address validation only checks format, not deployment status. It cannot automatically categorize or organize bookmarks without user-defined tags—tagging is manual.

PLEASE NOTE

This is a read-only tool for bookmark management—it never signs transactions. All data is stored in memory only and will be lost on page reload. The tool supports EVM chains only—Ethereum, Polygon, BSC, Arbitrum, Optimism, Base, and their testnets. Bookmark verification uses the connected provider—ensure you are on the correct network when verifying addresses. The tool is designed for development convenience—regularly export or save your bookmarks externally if needed.