What makes a password strong?
Two things: length and randomness. Every extra character
multiplies the number of guesses an attacker needs, which is why a 16-character random
password is astronomically harder to crack than an 8-character "clever" one. And randomness
matters because humans are predictable — names, birthdays, keyboard walks like qwerty123, and word-plus-number patterns like Summer2026! are the
first things cracking software tries.
A password like k7#mQpX2$vLn9wRt has neither problem: it's long, and every
character is chosen by a cryptographic random number generator with no pattern to exploit.
Password length vs. time to crack
Rough offline-attack estimates for random passwords using letters, numbers and symbols (modern GPU hardware, ~10 billion guesses per second):
| Length | Possible combinations | Time to crack |
|---|---|---|
| 8 characters | ~6 × 10¹⁵ | hours to days |
| 12 characters | ~5 × 10²³ | thousands of years |
| 16 characters | ~4 × 10³¹ | billions of years |
| 20 characters | ~4 × 10³⁹ | longer than the universe has existed |
That's why the slider above defaults to 16. Wondering about a password you already use? Test it with our password strength checker.
Three rules that prevent almost every account takeover
- Unique password per account. Reused passwords are how one site's breach becomes your email, bank and social accounts falling in the same week.
- 16+ random characters for anything that matters — generated, not invented.
- Turn on two-factor authentication. Even a stolen password fails without the 6-digit code. DroidPass includes a built-in 2FA authenticator, so codes live next to your logins.
Generated a password? Don't lose it.
Save it in DroidPass — an AES-256 encrypted vault with fingerprint unlock, a built-in 2FA authenticator, and offline access. Free to start.
What to look for in a free password generator
Most password generator pages are fine at the maths and differ in everything around it. Here is how this one is built, so you can compare it with whatever else is in your search results.
| What matters | This generator |
|---|---|
| Where the password is made | In your browser, with crypto.getRandomValues. Nothing is sent to a server. |
| Uniform randomness | Each character is picked with rejection sampling, so a 32-bit random value is never folded unevenly onto the character set (the "modulo bias" that many generators have). |
| Length | 8 to 128 characters. Use 16 or more for anything that matters. |
| Character sets | Uppercase, lowercase, numbers and symbols, each switchable. Every set you enable appears at least once, and the result is shuffled with the same CSPRNG so those characters never sit in fixed positions. |
| Strength readout | Real entropy in bits: length × log2(character set size), not a guess based on "looks complex". |
| Account, sign-up, ads | None. No login wall, no newsletter prompt, no ads on this page. |
| Copying | One tap. Paste it into the site, then save it in a password manager. |
| Passphrases | The DroidPass app generates memorable passphrases as well as random strings and saves them into your encrypted vault. |
Password generator FAQ
What is the best free password generator?
Any generator that (1) creates the password on your own device with a cryptographically secure random number generator, (2) lets you choose at least 16 characters with letters, numbers and symbols, and (3) does not need an account or show ads. This page does all three: it uses the Web Crypto API in your browser with rejection sampling, guarantees every character type you enable, goes up to 128 characters, and sends nothing to any server. The generator inside the DroidPass app adds memorable passphrases and saves the result straight into your encrypted vault.
Is this password generator safe to use?
Yes. Passwords are generated entirely in your browser using the Web Crypto API (crypto.getRandomValues), a cryptographically secure random number generator. Nothing you generate is ever sent to our servers, stored, or logged — you can even load this page and then go offline before generating.
How long should my password be?
At least 16 characters for anything important. Length beats complexity: a 16-character random password with letters, numbers and symbols would take centuries to brute-force, while an 8-character one can fall in hours. For master passwords and email accounts, 20+ characters is a good habit.
Should I use a different password for every account?
Yes — this is the single most important password rule. When one website leaks, attackers immediately try the same email and password everywhere else (credential stuffing). Unique passwords contain the damage to one account. A password manager exists precisely so you never have to remember them.
How do I remember a random password?
You don't. Generate it, then save it in a password manager like DroidPass — your vault is encrypted with AES-256 and unlocks with your fingerprint or Master PIN. The only password you ever memorize is the one that opens your vault.
Keep reading
How strong is my password? Test it →
Why you need a password manager in 2026 →
Offline password manager: access your passwords without internet →