How Strong is Your Password? Check Password Strength & Improve Security

Published May 3, 2026

Passwords are still the most common authentication method in 2026 - but most people are terrible at creating them. A weak password can be cracked in seconds. This guide shows you how password strength is measured, what to avoid, and how to create passwords that actually protect your accounts.

Test any password instantly with our free Password Strength Checker - it runs locally in your browser, so your password never leaves your device.

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What Makes a Password Strong?

Password strength is measured by entropy - essentially, how many guesses an attacker needs to crack it. Entropy depends on three factors:

Length - Every additional character multiplies the possible combinations exponentially
Character variety - Using uppercase, lowercase, numbers, and symbols increases the search space
Unpredictability - Dictionary words, common patterns, and personal info reduce effective strength

Entropy Score Reference

Entropy (bits)	Strength	Time to Crack (offline)	Example
< 28	Very Weak	Seconds	`password123`
28-35	Weak	Minutes	`Summer2024!`
36-59	Moderate	Hours to Days	`Tr0ub4dor&3`
60-79	Strong	Years	`correct-horse-battery-staple`
80+	Very Strong	Centuries	`kD9#mP2$xL7@qR5`

Common Password Mistakes

Using personal info - Birthdays, names, pet names, and phone numbers are the first things attackers try
Keyboard patterns - qwerty, 123456, and asdfgh are in every crack dictionary
Reusing passwords - A breach on one site compromises all your accounts
Simple substitutions - Changing o to 0 or e to 3 is well-known by cracking tools
Short passwords - Any password under 12 characters can be brute-forced with modern hardware

How Password Strength Checkers Work

A good password strength checker evaluates multiple factors:

Entropy calculation - Mathematical estimate of randomness
Pattern detection - Identifies keyboard walks, repeated chars, and sequential patterns
Dictionary matching - Checks against common passwords and word lists
Character set diversity - Rewards using multiple character types

Our Password Strength Checker does all of this locally in your browser. No data sent to any server - your passwords stay private.

How to Create Strong, Memorable Passwords

The Diceware Method (Recommended)

Pick 4-6 random words using dice or a random generator. The result is both strong and memorizable:

correct-horse-battery-staple

This 28-character password has ~70 bits of entropy - despite being easy to remember, it would take centuries to crack.

Use a Password Manager

Password managers generate and store cryptographically random passwords for each site. You only need to remember one master password. Our Password Generator creates strong random passwords you can save to any manager.

Minimum Requirements for 2026

At least 16 characters (12 absolute minimum)
Mix of uppercase, lowercase, numbers, and symbols
No dictionary words alone (use combinations)
Unique per site or service

Related Tools

Password Strength Checker - Test your passwords for free
Password Generator - Create strong random passwords
Hash Generator - Hash passwords with SHA-256, SHA-512, MD5
Basic Auth Header Generator - Generate HTTP auth credentials

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Last updated: May 3, 2026