Strong password generator

Make a strong, random password in your browser, choose its length and the characters it uses, and see how hard it would be to guess before you copy it.

Free
No account
Runs in your browser

Make a strong password

Move the length or switch a character set and a fresh password appears. It never leaves your browser.

Everything stays in your browser. Nothing is sent or saved.

How to use the password generator

Set the length. 16 characters or more is a good default for anything that matters.
Switch uppercase letters, numbers and symbols on or off to match what the site accepts. Every set you switch on appears at least once.
Check the strength read under the password: aim for Strong or Excellent.
Copy it straight into your password manager, or press Regenerate if you’d like another.

How the password generator works

The password holds at least one character from every set you switch on, each at a random place, and the rest are picked at random from all of them, using your browser’s cryptographic random number generator. Characters that are easy to mix up, like l, I, O, 0 and 1, are left out, so a password read aloud or typed from a screen comes out right.

Alphabetlowercase + the uppercase, numbers and symbols you switch on

Entropylength × log₂(alphabet size), in bits

Strengthunder 50 bits weak, 50 fair, 80 strong, 110 and up excellent

Entropy counts how many guesses an attacker would need to try every password the generator could have made. Each extra bit doubles it, which is why length beats cleverness: one more character adds more than swapping a letter for a symbol ever could.

Worked example: the generator’s starting settings

Length: 18 characters
Alphabet: 25 + 24 + 8 + 13 = 70 characters
18 × log₂(70): ≈ 110 bits
Strength: Excellent (≈ 110 bits)

At a trillion guesses a second, trying every 18-character password from that alphabet would take about 50 trillion years, thousands of times the age of the universe.

Password generator FAQ

How long should a password be?

For accounts that matter, 16 characters or more from a mix of letters, numbers and symbols. Length counts for more than anything else, and a password manager remembers it for you, so there is no reason to go short.

Is it safe to make a password on a website?

On this one, yes. The password is made in your browser by its cryptographic random number generator, and it is never sent to our server or stored. Copy it into your password manager and it exists nowhere else.

What do the bits of entropy mean?

They measure how many guesses it would take to try every password the generator could have made with your settings. 50 bits is about a quadrillion guesses, and each extra bit doubles that. The read is honest about a random password, not about one you made up yourself.

How do I share a password with a client?

Never in the same email as the username. Use your password manager’s sharing, or send it over a different channel, and ask the client to change it after the first sign-in. If it goes into a database or mail server link, encode it first with the URL encoder, or its symbols will break the link.

Is a passphrase better than a password?

For the one password you have to remember, often. Five words picked at random from a long list, like the Diceware list, give about 64 bits and are easier to type. Random words, though, not a favorite quote. If a site sets a maximum length, check yours with the word counter.

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