Generate 12 Word Seed Phrase

WHAT IT DOES

This tool generates a cryptographically secure 12-word seed phrase (mnemonic) using the BIP39 standard, the same protocol used by most Ethereum and EVM-compatible wallets. Each phrase consists of 12 words randomly selected from a fixed wordlist of 2048 words, providing 128 bits of entropy. The tool displays the generated phrase with numbered words for easy reading, along with the entropy hex and checksum for verification purposes.

All generation operations are performed entirely in your browser using the ethers.js library. No data is ever transmitted to any server, stored in cookies, or logged. The seed phrase appears only on your screen and is never saved anywhere. You can generate as many phrases as you want, each one being unique and cryptographically independent from the others.

HOW TO USE

Open the tool and click the "generate new seed phrase" button. A fresh 12-word seed phrase will appear in the text area, numbered from 1 to 12 for easy reading. The entropy hex and checksum values are also displayed for advanced verification. Copy the phrase and store it securely offline — we recommend writing it down on paper or storing it in a hardware encrypted device.

The tool works without requiring any wallet connection, though connecting your wallet shows your current address and chain ID for reference. You can generate unlimited phrases, and each one is completely independent from the previous ones. The phrase can be used with any BIP39-compatible wallet to create a new Ethereum or EVM wallet address.

TECHNICAL MECHANISM — CRYPTOGRAPHICALLY SECURE GENERATION

The tool uses the ethers.js library's randomBytes(16) function to generate 16 bytes (128 bits) of entropy from the browser's built-in cryptographic random number generator (Crypto.getRandomValues()). This entropy is then passed through the BIP39 algorithm, which divides the entropy into groups of 11 bits, maps each group to a word in the BIP39 wordlist of 2048 words, and appends a 4-bit checksum derived from the SHA-256 hash of the entropy to ensure validity.

The resulting 12-word phrase has approximately 2^128 possible combinations, making it practically impossible to guess or brute force. The tool also verifies the generated mnemonic using isValidMnemonic() to ensure it passes the BIP39 checksum verification. The entropy hex and checksum are displayed alongside the phrase for users who want to verify the generation process independently.

WHAT IT CANNOT SEE

This tool cannot verify the generated seed phrase against any blockchain or network, as it operates entirely offline. It cannot display wallet balances, transaction history, or any on-chain data associated with the phrase. It cannot interact with non-EVM chains or derive addresses for Bitcoin, Solana, Cosmos, or other non-EVM networks. The tool cannot recover lost seed phrases or help you remember a phrase you have forgotten. It also cannot ensure the security of the generated phrase if your device is compromised with malware, keyloggers, or screen capture software.

PLEASE NOTE — EVM CHAINS ONLY

The BIP39 seed phrase generated by this tool is compatible with all Ethereum Virtual Machine (EVM) wallets and networks, including Ethereum, Polygon, Arbitrum, Optimism, Avalanche, BNB Smart Chain, and Base. However, the tool does not derive the actual wallet address from the seed phrase — it only generates the phrase itself. To create a wallet, you must import this phrase into a compatible wallet application. This tool does not support non-EVM chains or wallets that use different derivation paths or mnemonic standards.