Utility
XS complexity

Secure Password & Seed Generator.

Generate cryptographically random passwords, Diceware-style passphrases, and BIP-39 seed phrases directly in your browser. Shows entropy in bits. Nothing leaves your device.

Free Runs in your browser Data: crypto.getRandomValues (browser)
Step 1 of 3Password Generator
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Choose type
What kind of secret do you need?

Understanding your results.

The output shows three types of generated secrets depending on the mode you choose:

  • Random password — cryptographically random characters with configurable length and symbol sets. Includes entropy display so you know the strength.
  • Diceware passphrase — common words combined into a phrase that is strong yet memorable. Each word adds ~13 bits of entropy.
  • BIP-39 seed phrase — standard 12/15/18/21/24-word recovery phrases compatible with hardware wallets. For testing and demo only — do not use with real funds unless you understand key management.

Common mistake: using a generated password once and forgetting to save it. Always store generated passwords in a password manager (Bitwarden, 1Password, KeePass) immediately after generation.

How to use this tool.

Pick your mode: random password (up to 128 characters with configurable symbol sets), Diceware passphrase (common-word combinations for memorability), or BIP-39 seed phrase (the standard 12/15/18/21/24-word recovery phrases used by hardware wallets).

Every output is generated client-side using your browser's cryptographically secure random number generator (crypto.getRandomValues). Nothing is sent to a server, nothing is logged, and the page does not persist state.

Affiliate disclosure: Some links on this page are affiliate links. If you click through and make a purchase, AHCrypto may earn a commission at no additional cost to you. We only recommend services we have tested and verified.

Privacy & safety.

Your privacy matters. All generation happens client-side using your browser's crypto.getRandomValues API. Nothing is sent to any server, logged, or stored. You can disconnect from the internet and the tool still works.

Never paste a real wallet seed phrase. The BIP-39 phrases generated here are for testing and demonstration. Never use a seed phrase generated on any website to secure real cryptocurrency funds. For real wallets, always generate the seed phrase directly on a hardware wallet device (like Ledger) or a trusted, air-gapped software wallet.

Use a password manager. Generated passwords are only as secure as how you store them. Copy them immediately into a password manager (Bitwarden, 1Password, or KeePass). Do not store them in plain text files, notes apps, or browser storage.

Frequently asked questions.

How secure are randomly generated passwords?
Very secure when generated properly. Our tool uses your browser's <code>crypto.getRandomValues</code> API, which is cryptographically secure — the same randomness used for TLS encryption. A 16-character password with mixed case, digits, and symbols has approximately 2^96 possible combinations, making it infeasible to brute force with current technology.
What is a Diceware passphrase?
Diceware is a method for creating memorable but secure passphrases by combining random words from a word list. Each word adds about 13 bits of entropy. A 6-word Diceware passphrase (78 bits) is strong against brute force but much easier to remember than a random string of characters. Our implementation uses the standard EFF word list.
What's the difference between a seed phrase and a password?
A seed phrase (or recovery phrase) is a set of 12, 18, or 24 words from the BIP-39 standard used to recover cryptocurrency wallets. It is not a password — it is the master key to your wallet. A password is an authentication secret for logging into accounts. Never use the same seed phrase as a password, and never enter a real seed phrase into any website.
What is entropy and why does it matter?
Entropy measures how unpredictable a secret is, expressed in bits. Each bit of entropy doubles the difficulty of guessing the secret. A password with 40 bits of entropy can be cracked instantly by a modern computer. We recommend at least 80 bits for important accounts and 128+ bits for master passwords / seed phrases. Our tool displays the entropy of every generated output.
Is a longer password always better?
Yes, length matters more than complexity. A 20-character lowercase-only password (95 bits) is stronger than a 10-character password with symbols and numbers (66 bits), and much easier to type. The critical factor is that the password is generated randomly and not based on dictionary words (unless using Diceware).
Can I use these generated passwords in real wallets?
You can use generated passwords to secure your exchange or wallet login credentials. However, BIP-39 seed phrases generated by this tool should only be used for testing or demonstration unless you fully understand key management, including how to securely store and back up the phrase. For real funds, always generate your seed phrase on a hardware wallet like Ledger.
What is k-anonymity and how does the breach check use it?
Our linked <a href="/tools/breach/" class="text-brand-teal hover:underline">breach checker</a> uses k-anonymity: your full password never leaves your device. Only the first 5 characters of the SHA-1 hash are sent to HaveIBeenPwned, which returns a list of hash suffixes that match. Your full password is matched against those suffixes locally. This means even if the API were compromised, an attacker could only know the first 5 hash characters — not your password.
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