Security & Authentication Tools

Password Strength Checker

Instantly check how strong a password is, right in your browser - never sent anywhere.

Type a password below to instantly check its strength - entirely in your browser, your password is never sent anywhere, not even to us.

Enter a password to check

Checked entirely in your browser - never sent anywhere, not even to us.

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JustChecker builds tools that respect your data - this one never leaves your browser.

What Is the Password Strength Checker?

It estimates how hard a password would be to guess, looking at length, character variety and common weak patterns. The check runs entirely in your browser - the password is never sent anywhere.

When to Use It

When choosing a new password.
To show others why short or predictable passwords are weak.

How to Use It

Type a password (preferably a test one similar to what you plan to use).
Read the rating and suggestions.

Understanding the Result

Length matters most: a long passphrase of random words beats a short password full of symbols. Avoid names, dates, keyboard patterns and reused passwords.

Limitations

No checker can know if a password has been leaked. Use a password manager and unique passwords - generate one with the Secure Password Generator.

Examples

Password	Why	Strength
`Password@123`	A common word with the usual substitutions - in every cracking list	Weak
`Asha1990!`	Name + year + symbol, easy to guess with personal information	Weak
`q7#Vt!pL2x`	Random, but only 10 characters	Fair to good
`lamp-orbit-cactus-violin-harbor`	Five random words - long and memorable	Strong

What Makes a Password Strong

Length first: each extra character multiplies the number of guesses needed.
Randomness: chosen by a generator, not by you - people pick predictable patterns.
Uniqueness: one password per site, so one breach cannot unlock the others.

What a Checker Cannot Tell You

A password can score well and still be unsafe if it has already appeared in a data breach or you have used it before. Use a password manager, turn on two-factor authentication, and check breach services such as Have I Been Pwned.

Create a strong one with the Secure Password Generator, see the maths with the Password Entropy Calculator, and read how to create a strong password.

Frequently Asked Questions

No - this tool checks your password entirely in your browser using JavaScript. It is never transmitted anywhere, not even to us.

Length matters most - aim for at least 12-16 characters. Mixing uppercase, lowercase, numbers, and symbols helps, as does avoiding common words, keyboard patterns, and repeated characters.

Yes - a password manager can generate and store long, unique, random passwords for every account, which is far more secure than memorizing passwords yourself.