Seed Vault (BIP39)

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Generate BIP39 seed phrases directly in your browser using the Web Crypto API.

Seed (BIP39) is a human-readable backup phrase for your wallet private keys. You use it to recover your wallet on a new device or after loss/reset.
Important: Review the "Crypto Seed Best Practices" on the right (or scroll down on mobile) to protect your assets. Your device may not be secure. A few minutes of reading is better than losing everything.

How It Works

Entropy is generated with your browser CSPRNG (Web Crypto API).
BIP39 checksum is computed from SHA-256 before converting to 11-bit word indexes.
Validation checks both word presence and checksum correctness.

Crypto Seed Best Practices

  • Use a clean computer – a live USB with Tails OS or a machine that has never been online.
  • Use a clean browser in Private/Incognito mode – no extensions, no history.
  • Run completely offline – unplug the network cable, turn off WiFi before generating a new seed phrase.
  • Write by hand on paper (or metal), never keep only digital screenshots (even copy to clipboard).
  • Clear state after writing the seed – close the Private/Incognito browser.
  • Create 2-3 backups and store in separate safe locations (home safe, bank box).
  • Consider adding a BIP39 passphrase for an extra security layer.
  • Practice wallet recovery on an offline spare device before storing large funds.