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BIP39 Mnemonic Generator

BIP39 Mnemonic Generator

Generate and validate BIP39 seed phrases locally

For testing and development only. Never use a generated phrase for a real wallet holding funds, and never paste a real recovery phrase into any website.

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Validate a phrase

About

Generate a BIP39 mnemonic seed phrase (12, 15, 18, 21, or 24 words) using a cryptographically secure random number source, or validate an existing phrase (its checksum is checked). Entropy is shown alongside. Everything runs locally in your browser — no phrase is transmitted or stored. For testing and development only.

    Related guides

    How BIP39 Seed Phrases Work (and Why You Must Never Reuse One)

    The entropy-to-words mapping, the checksum, and the security model that makes a 12-word phrase protect an entire cryptocurrency wallet.

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