BIP39 Mnemonic Generator
Generate cryptographically secure BIP39 mnemonic phrases (12 or 24 words) and validate existing ones. Runs 100% in your browser — your seed phrase never leaves your device.
Important security warnings
- Never use a mnemonic generated on ANY website for real funds. This tool is for education and testing only.
- Never share your mnemonic with anyone, ever. It gives complete control of your wallet.
- Never save your mnemonic to localStorage, cloud storage, email, or screenshots.
- Never use this on a compromised or public computer.
- For real wallets, generate offline using hardware wallets (Ledger, Trezor) or trusted offline tools.
Generate and validate BIP39 mnemonic seed phrases entirely in your browser with SolveBar's BIP39 Generator. Uses the browser's cryptographic random number generator for secure phrase generation. For educational and testing purposes only — never use browser-generated phrases for real funds.
What is BIP39?
BIP39 defines a standard for encoding cryptographic seeds as human-readable word sequences. A 12-word phrase encodes 128 bits of entropy, while 24 words encodes 256 bits. The words are chosen from a standardized list of 2048 English words.
How BIP39 derives wallet keys
The mnemonic phrase is converted to a seed using PBKDF2 with 2048 iterations of HMAC-SHA512. This seed is then used with BIP32/BIP44 to derive a hierarchical tree of key pairs. The same 12-24 words will always recreate the same wallet across any compatible wallet software.
Security warnings for real use
Never generate real wallet mnemonics in a browser. Use a hardware wallet (Ledger, Trezor) or an air-gapped device for real wallets. Never enter your real seed phrase into any website. Never store your seed phrase digitally — write it on paper and store it securely offline.
Frequently Asked Questions
Is this safe to use for a real wallet?
No. This tool is for education and testing only. For real wallets, generate your seed phrase using a hardware wallet or trusted offline tool with no internet connection.
Can I validate an existing mnemonic without entering it online?
For security, validate your real mnemonic offline using a trusted tool. The validator here is suitable for testing generated test phrases, not for your real wallet seed.
What is the difference between 12 and 24 word phrases?
12 words provide 128 bits of entropy — mathematically impossible to brute-force. 24 words provide 256 bits. In practice both are secure.