What character sets can I include in a generated password?

You can toggle four character sets independently: uppercase letters (A–Z, 26 characters), lowercase letters (a–z, 26 characters), numbers (0–9, 10 characters), and symbols (!@#$%^&*()_+-=[]{}|;:,.<>?, 32 characters). At least one character type must be selected, and every checked type is guaranteed to appear at least once in each generated password.

What does "Exclude ambiguous characters" do?

It removes visually similar characters — 0 (zero), O (capital O), 1 (one), l (lowercase L), and I (capital I) — from the available character pool. This is useful when a password needs to be typed manually or read off a printed page, since it reduces transcription errors at the cost of a very slightly smaller character set and marginally lower entropy.

Can I generate more than one password at once?

Yes. The "How Many Passwords?" field lets you generate up to 10 independent passwords in a single click, each generated separately using the same cryptographically secure random source and your selected character-set options.

What is the difference between Math.random() and crypto.getRandomValues()?

Math.random() is a fast, general-purpose pseudo-random number generator not designed for security — its internal state can potentially be inferred from enough outputs. crypto.getRandomValues(), part of the Web Cryptography API, draws from the operating system's cryptographically secure random number source, the same category of randomness used by password managers and encryption software. This generator uses crypto.getRandomValues() exclusively, with rejection sampling to remove modulo bias.

Should I use a password manager to store my generated passwords?

Yes, strongly recommended. A randomly generated password is only as safe as where you keep it afterward — a reputable password manager stores each password encrypted, fills it in automatically, and lets you use a unique password per site without needing to memorize any of them. Avoid storing generated passwords in plain-text notes, spreadsheets, or unencrypted files.

Will every website accept a randomly generated password?

Usually, but not always. Some websites impose their own rules — a maximum length shorter than you generated, a restricted symbol set, or a requirement to avoid certain punctuation. If a generated password is rejected, try regenerating with a shorter length, fewer symbol types, or the "exclude ambiguous characters" option, then check the site's specific password policy.

Does a longer password always beat a more complex one?

Generally yes, when comparing realistic options. Adding characters multiplies the keyspace exponentially regardless of character variety, while adding a character type only multiplies it by a small constant factor. For example, extending a lowercase-only password by a few characters typically adds more entropy than adding symbols to a shorter password — length dominates, though combining both length and variety gives the strongest result.

Password Generator — Secure Passwords, Passphrases & Strength Checker

🔐 Password Generator

Password Length

Uppercase letters (A–Z)

Lowercase letters (a–z)

Numbers (0–9)

Symbols (!@#$%...)

Exclude ambiguous characters (0, O, 1, l, I)

How Many Passwords?

Generated Passwords

Strength (first password)

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🔐

Choose your options and click Generate

🗝️ Passphrase Generator

Number of Words

Word Separator

Capitalize each word

Add a random number at the end

Generated Passphrase

Passphrase

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Entropy

—

Word List Size

—

🗝️

Choose your options and click Generate

🛡️ Password Strength Checker

Enter a Password

Analyzed entirely in your browser — nothing is sent anywhere.

Analysis

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Length

—

Character Types

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Est. Crack Time

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🛡️

Type a password to see its strength analysis

Guide

About the Password Generator

This free password generator online bundles three things people need for password security: a secure password generator and random password generator for generating a strong password generator-grade string, a memorable passphrase generator built on diceware passphrase principles, and a password strength checker that scores any password you type. Everything runs entirely inside your browser — no password, passphrase, or keystroke is ever sent to a server, logged, or stored, so it also works as a private, offline-friendly password security checker.

How It Works

The Password Generator lets you generate random password strings from your chosen character types (uppercase, lowercase, numbers, symbols) using the browser's crypto.getRandomValues() cryptographically secure random source with rejection sampling, avoiding the bias that weaker generators like Math.random() can introduce. The Passphrase Generator strings together several random dictionary words — the same diceware passphrase approach used by security professionals — optionally capitalized and numbered, for a secure passphrase that's both strong and easy to type from memory. The Strength Checker doubles as a password entropy calculator and crack time calculator: it estimates entropy in bits (length × log₂ of the character set size) and flags known common passwords, which are crackable almost instantly by a real crack time calculator estimate regardless of their apparent complexity.

Why It Matters

Weak, reused, or predictable passwords remain one of the leading causes of account compromise. A single strong, unique password per account — generated randomly by a secure password generator rather than chosen by a human, who tends to pick predictable patterns — closes off the most common attack paths, including credential stuffing and dictionary attacks.

Tips for Accurate Results

Use 16+ characters or 4+ random words where a site allows it — length is the single biggest factor in resisting brute-force attacks, whether you generate random password strings or a diceware passphrase
Store generated passwords in a reputable password manager rather than reusing or memorizing them across sites
Prefer a secure passphrase for master passwords you type often by hand, since it's easier to enter accurately than a random symbol string
Run any existing password through the password strength checker before reusing it elsewhere — a password can look complex and still be a known common one
Treat the crack time calculator estimate as a lower bound, not a guarantee — attacker hardware and technique both improve over time, so favor a strong password generator result with margin to spare

About

How This Password Generator Works

🎲

Cryptographically Secure Randomness

Every character and word is chosen using crypto.getRandomValues() — the same secure random source used by password managers — with rejection sampling to eliminate bias, rather than the weaker Math.random().

📊

Entropy & Crack Time

Entropy (in bits) measures how unpredictable a password is: length × log₂(character set size). Crack time estimates assume a fast offline attack and roughly double for every extra bit of entropy.

🧩

Passphrases vs Passwords

A passphrase built from several random dictionary words can carry more entropy than a shorter complex password, while being much easier for a human to remember and type accurately.

🔒

Nothing Ever Leaves Your Browser

Generation and analysis run entirely in client-side JavaScript. No password, passphrase, or keystroke is transmitted to a server, logged, or stored — refreshing the page discards everything.

FAQ

Frequently Asked Questions

Common questions about password security

Is this password generator actually secure?

Yes. It uses your browser's crypto.getRandomValues() API — a cryptographically secure pseudo-random number generator (CSPRNG) — with rejection sampling to avoid bias, the same approach used by password managers. Nothing is ever transmitted: all generation happens locally in your browser and no password is sent to any server or stored anywhere.

How long should my password be?

Most current guidance (including NIST) recommends at least 12–16 characters using a mix of character types, or longer if only using letters. Longer passwords are exponentially harder to crack — each additional character multiplies the possible combinations by the size of your character set.

What is password entropy and how is it calculated?

Entropy measures unpredictability in bits: entropy = length × log₂(character set size). A 12-character password using lowercase, uppercase, numbers and symbols (94 possible characters) has about 12 × log₂(94) ≈ 78.7 bits of entropy. Higher entropy means exponentially more possible combinations to guess.

Should I use a password or a passphrase?

A passphrase (several random words strung together, like "correct-horse-battery-staple") can be just as strong as a complex password while being far easier to remember and type. Four random words from a large word list typically provide more entropy than an 8-character complex password, and passphrases are excellent for master passwords you type often.

Why does this tool warn about common passwords?

Attackers don't guess randomly — they try lists of the most commonly used passwords first (like "password123" or "qwerty"). A password can have decent mathematical entropy and still be extremely weak in practice if it's a known common password, so the Strength Checker flags these regardless of length.

Is this tool suitable for use in any country?

Yes. Password strength depends only on mathematics (character sets and length), not on any region-specific standard, so this generator and strength checker work identically and securely no matter where you are. All processing happens locally in your browser — nothing is sent over the internet, so there are no regional data-transfer or privacy concerns.

Does this website store or see my generated passwords?

No. Password generation, the strength checker, and the copy-to-clipboard button all run entirely in JavaScript inside your own browser. Nothing is logged, transmitted to a server, or saved — closing or refreshing the page permanently discards everything.