BIP39 Mnemonic Generator & Validator - Seed Phrase Generator | 8gwifi.org

BIP39 Mnemonic Generator & Validator

Generate and validate BIP39 mnemonic seed phrases for cryptocurrency wallets. Supports 12-24 word phrases.

Security Warning: This tool is for educational purposes. For real cryptocurrency wallets, generate mnemonics offline on an air-gapped computer or use a hardware wallet. Never share your mnemonic with anyone!

Generate Mnemonic

Mnemonic Phrase

Click "Generate Mnemonic" to create a new seed phrase

Validate & Derive Seed

Leave empty if not using a passphrase
What is BIP39?

BIP39 (Bitcoin Improvement Proposal 39) is a standard for generating mnemonic phrases that represent cryptographic keys. It provides a human-readable way to backup and restore cryptocurrency wallets.

How it works:

  • Entropy: Random data (128-256 bits) is generated using a cryptographically secure random number generator
  • Checksum: A checksum is calculated from the entropy and appended to ensure data integrity
  • Word Mapping: The combined data is split into 11-bit segments, each mapped to a word from the BIP39 wordlist (2048 words)
  • Seed Derivation: The mnemonic + passphrase are processed through PBKDF2 to derive a 512-bit seed
  • Key Derivation: The seed is used with BIP32/BIP44 to generate hierarchical deterministic (HD) wallet keys

Security Levels:

  • 12 words: 128 bits of entropy = 2^128 combinations (340 undecillion)
  • 24 words: 256 bits of entropy = 2^256 combinations (more than atoms in universe)

Important Notes:

  • Anyone with your mnemonic can access your funds - keep it secret!
  • Write it down on paper and store in a secure location (safe, safety deposit box)
  • Never store mnemonics digitally (no photos, no cloud storage, no email)
  • The passphrase is optional but provides an additional security layer
  • BIP39 is supported by most modern cryptocurrency wallets

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