BIP-39 (Bitcoin Improvement Proposal 39) describes the implementation of a mnemonic sentence—a group of easy-to-remember words—for the generation of deterministic crypto wallets.

Is it safe to generate seed phrases here?

All generation and entropy calculation uses window.crypto.getRandomValues() and runs 100% locally inside your browser. No seed phrases are ever transmitted over the network.

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Cryptography

BIP-39 Mnemonic Generator

Generate and validate 12/24-word cryptocurrency mnemonic seed phrases.

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How to Use BIP-39 Mnemonic Generator

Choose the desired seed phrase length (12 words for 128-bit entropy or 24 words for 256-bit entropy).
Click Generate New to create a cryptographically secure mnemonic phrase.
Copy and securely write down the seed phrase on a physical medium.
Optionally paste existing seed phrases into the validator to check word validity.

Frequently Asked Questions

What is BIP-39?: BIP-39 (Bitcoin Improvement Proposal 39) describes the implementation of a mnemonic sentence—a group of easy-to-remember words—for the generation of deterministic crypto wallets.
Is it safe to generate seed phrases here?: All generation and entropy calculation uses window.crypto.getRandomValues() and runs 100% locally inside your browser. No seed phrases are ever transmitted over the network.

Sources & references

Primary references: BIP 0039: Mnemonic code for generating deterministic keys; W3C Web Cryptography API.

Review policy: references and behavior notes are checked whenever the tool implementation changes.