Multi-Chain Config File Generator

WHAT IT DOES

Multi-Chain Config File Generator creates structured configuration files for applications that need to interact with multiple EVM chains. You define chains with their names, chain IDs, RPC URLs, and native symbols, and optionally add contract addresses deployed on each chain. The tool generates configuration files in your choice of formats: JSON, YAML, .env (environment variables), or TOML. This is essential for developers building cross-chain applications, multi-chain frontends, indexers, or any project that needs to manage chain-specific settings and contract addresses across multiple networks. The generated configuration can be used directly in your application to connect to the right chains and contracts.

HOW TO USE

Enter a config name. Define your chains—one per line—in the format "name | chainId | rpcUrl | nativeSymbol". For example: "Ethereum | 1 | https://mainnet.infura.io/v3/KEY | ETH". Optionally add contract addresses—one per line—in the format "name | address | chainName". For example: "MyToken | 0x123... | Ethereum". Select your preferred output format (JSON, YAML, .env, or TOML). Click "Generate Config File." The tool builds a complete configuration file containing all chains and contract addresses in the selected format. A preview shows the configuration, and you can copy it to your clipboard or download it as a file. The .env format generates environment variables with chain-specific prefixes for easy integration with Node.js applications.

THE REAL MECHANISM

The tool uses a pure JavaScript template engine that operates entirely client-side. It parses the chain definitions by splitting each line on the pipe character to extract name, chain ID, RPC URL, and native symbol. Contract definitions are similarly parsed to extract contract name, address, and the chain it's deployed on. The tool validates that chain IDs are numbers and addresses are valid hex strings. Depending on the selected output format, it generates the configuration using different serializers: JSON.stringify for JSON, a custom YAML generator that handles nested objects, a .env generator that produces environment variables with chain-specific prefixes (e.g., ETHEREUM_RPC_URL), and a TOML generator that creates structured TOML tables. All processing is done in the browser—no data is sent to external servers.

WHAT IT CANNOT SEE

This tool cannot automatically detect chain IDs or RPC URLs without user input—you must provide them manually. It cannot generate configurations for non-EVM chains. It cannot validate that the RPC URLs are reachable or that the chain IDs are correct. It cannot generate environment-specific configuration automatically (e.g., development vs production). It cannot verify that contract addresses are valid on the specified chains or that the contracts are actually deployed. The tool does not fetch data from the blockchain or from any external source.

PLEASE NOTE

Multi-Chain Config File Generator works for any EVM-compatible chain and does not require a blockchain connection to function, though the network selector is provided for context. It is a configuration tool for developers, not an execution tool. It reads data only and does not send any information to external servers. The tool is free to use and does not require authentication. For best results, ensure your RPC URLs are correct and that contract addresses are valid on their respective chains.