Open-source blockchain utilities for EVM-compatible chains.
Keys, wallets, balances, and automation — all in your browser.
Web3ToolKit is a static web app that provides blockchain tools for EVM-compatible chains. It runs entirely in the browser — no backend, no server, no accounts. All blockchain calls go directly from the client via RPC.
Try it at w3tk.app or run it locally. It also ships as a native desktop app via Tauri.
| Tools Overview | Key Pair Generator |
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| Wei Converter | Automator |
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- Seed Phrase Generator — generate BIP-39 mnemonic phrases
- Key Pair Generator — generate private keys and public addresses
- Get Addresses from Seed Phrase — derive addresses from a mnemonic
- Get Addresses from Private Key — derive addresses from a private key
- Get Address and Keys from Seed Phrase — derive full key material from a mnemonic
- Import Wallet from JSON — import a V3 keystore file
- Export Wallet to JSON — export a private key to V3 keystore
- Get Balances — native + ERC-20 token balances
- Get Balances per Block — historical balance at specific block numbers
- Drain Funds — transfer all funds from one address to another
- Get Block — fetch block data by number or hash
- Get Transaction — fetch transaction details
- ERC-20 Token Info — read token name, symbol, decimals, supply
- ENS Resolver — forward + reverse ENS lookups
- Is Valid Seed Phrase — validate a BIP-39 mnemonic
- Is Valid Address — validate an Ethereum address
- Wei Converter — convert between Wei, Gwei, and Ether
| Mainnets | Testnets |
|---|---|
| Arbitrum | Arbitrum Sepolia |
| Avalanche | Avalanche Fuji |
| Base | Base Sepolia |
| BNB Chain | BNB Testnet |
| Ethereum | Ethereum Sepolia |
| Gnosis | Gnosis Chiado |
| Optimism | Optimism Sepolia |
| Polygon | Polygon Amoy |
Custom networks can be added via the UI and are persisted in localStorage.
pnpm install
pnpm devOpen http://localhost:3000.
Web3ToolKit is also available as a native desktop app built with Tauri, wrapping the static site in a lightweight native webview.
pnpm startServes the out/ directory using npx serve.
pnpm test # run all tests
pnpm test:watch # watch modepnpm lint