BIP39 Mnemonic Generator
BIP39 Mnemonic Generator is a free online crypto that helps you generate a BIP39 mnemonic seed phrase (12/15/18/21/24 words) and the corresponding entropy + seed; or convert an existing mnemonic to its seed. BIP39 Mnemonic Generator uses 4 input fields, returns 4 output values, and runs in your browser on the device.
Key facts
- Inputs
- 4 fields: Mode, Word count (generate only), Existing mnemonic (decode mode), and Passphrase (optional)
- Outputs
- 4 values: Mnemonic, Entropy (hex), Seed (hex, 64 bytes), and Summary
- Runtime
- your browser on the device
- Mode
- Crypto
- Privacy
- Files and text stay in the browser session.
- Cost
- $0, no account required
How to use BIP39 Mnemonic Generator
- 1
Paste or fill in the input
Enter your text or values into the input fields on the page.
- 2
Run the utility
Click Compute to run the utility in your browser and review the result.
- 3
Copy the output
Copy the output value you need from the result panel.
BIP39 Mnemonic Generator details
First, enter Mode in BIP39 Mnemonic Generator. Next, review Mnemonic, Entropy (hex), Seed (hex, 64 bytes), and Summary. Additionally, BIP39 Mnemonic Generator uses 4 input fields and 4 output blocks so the result is easy to scan and copy.
BIP39 is the standard that bitcoin and most other cryptocurrency wallets use to encode random entropy as a human-friendly word list. Pick a word count (12 words = 128 bits of entropy, 24 = 256 bits) and we'll roll fresh randomness via crypto.getRandomValues, derive the BIP39 checksum, and look up the matching words from the English wordlist. The seed (hex) is what wallets actually use to derive HD-wallet master keys (BIP32). You can also paste an existing mnemonic (with an optional passphrase) to compute the seed without generating new entropy. Runs entirely in your browser; your seed phrase never leaves this device.
Common searches
- bip39 mnemonic generator
- bip39 seed phrase generator
- bitcoin seed phrase generator
- crypto wallet recovery phrase
- bip39 to seed
- bip39 mnemonic
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Frequently asked
What is BIP39 Mnemonic Generator?
BIP39 Mnemonic Generator is a free online crypto that helps you generate a BIP39 mnemonic seed phrase (12/15/18/21/24 words) and the corresponding entropy + seed; or convert an existing mnemonic to its seed. BIP39 Mnemonic Generator uses 4 input fields, returns 4 output values, and runs in your browser on the device.
What inputs and outputs does BIP39 Mnemonic Generator use?
BIP39 Mnemonic Generator uses 4 input fields: Mode, Word count (generate only), Existing mnemonic (decode mode), and Passphrase (optional). BIP39 Mnemonic Generator returns 4 output values: Mnemonic, Entropy (hex), Seed (hex, 64 bytes), and Summary.
Do my files and data stay private?
Yes. BIP39 Mnemonic Generator runs entirely in your browser using your device's CPU. Files and text are never uploaded to our servers, so your data stays private.
How do I use BIP39 Mnemonic Generator?
Open BIP39 Mnemonic Generator, paste or fill in the input fields, and the result updates instantly. BIP39 Mnemonic Generator runs in your browser with no upload and no waiting.
Which browsers does BIP39 Mnemonic Generator support?
Any modern browser works in Chrome, Firefox, Safari, and Edge on desktop and mobile. BIP39 Mnemonic Generator uses standard web APIs and does not require any plugin, extension, or sign-up.