How Strong Is My Password?
Test your password strength instantly. Our free checker scores your password from 0 to 100, estimates crack time, and gives you actionable tips to improve security. Everything runs locally in your browser — your password is never sent anywhere.
How Our Password Strength Checker Works
Six independent checks combine into a single 0-100 score so you can see exactly where your password is strong — and where it falls short.
Password Length Analysis
Length is the single biggest factor in password security. Every additional character exponentially increases the number of possible combinations an attacker must try. Our checker awards up to 30 points for length, with full marks at 20 or more characters. Passwords shorter than 8 characters are flagged as dangerously weak regardless of complexity.
Character Diversity
Using a mix of lowercase letters, uppercase letters, numbers, and special characters dramatically increases the size of the character set an attacker must search. A password using all four types draws from a pool of 95 characters instead of just 26. We award up to 25 points for diversity, with a bonus for using all four types together.
Common Password Detection
Attackers don't start with random guesses — they start with lists of the most commonly used passwords. Our tool checks your password against the top 200 most breached passwords, including leet-speak variants like "p@ssw0rd" and "l3tm3in." If your password appears on these lists, it can be cracked in seconds regardless of its length.
Pattern Recognition
Keyboard walks like "qwerty" and "asdfgh," sequential runs like "abcdef" and "123456," repeated characters, and date patterns are all shortcuts that attackers exploit. Our pattern engine detects these predictable sequences and deducts points when they appear, even when they are embedded inside a longer password.
Entropy & Crack Time
Entropy measures the theoretical randomness of your password in bits. We calculate entropy based on character set size and length, then estimate how long a brute-force attack would take at 10 billion guesses per second — a realistic rate for modern GPU clusters. The result ranges from "Instant" for trivial passwords to "Centuries+" for strong ones.
100% Browser-Based Privacy
Unlike many online password checkers, this tool never sends your password to a server. Every calculation runs locally in your browser using JavaScript. No network requests, no logging, no analytics on what you type. You can disconnect from the internet and the tool works exactly the same. Your password stays on your device — always.
Why Password Strength Matters
Weak passwords are the leading cause of data breaches. According to security research, over 80% of hacking-related breaches involve compromised credentials. Attackers use automated tools that can test billions of password combinations per second, making short or predictable passwords essentially worthless as a security measure.
A truly strong password combines length, randomness, and character diversity. The best approach is to use a unique password for every account — ideally generated and stored by a password manager — and to enable two-factor authentication wherever possible. Our tool helps you evaluate your current passwords and understand exactly what makes them strong or weak so you can take action.
For a deeper understanding of online threats, read our guides on how to identify phishing links before you click and understanding SSL certificates and why they matter. Strong passwords are just one layer of defense — staying informed about phishing, encryption, and safe browsing habits keeps you protected across the board.
Related Security Guides
Learn more about protecting yourself online.
How to Identify Phishing Links Before You Click
Learn the key warning signs of phishing URLs and how to protect yourself from malicious links online.
Read articleUnderstanding SSL Certificates and Why They Matter
A beginner-friendly guide to SSL certificates, how they work, and why they are essential for online safety.
Read articleFrequently Asked Questions
Everything you need to know about password strength, security, and staying safe online.
Enter your password in the checker above to get an instant strength score from 0 to 100. Our tool analyzes six key factors — length, character diversity, uniqueness, common password lists, predictable patterns, and estimated crack time — to give you a comprehensive strength rating from Very Weak to Strong.
A strong password is at least 12 characters long and uses a mix of uppercase letters, lowercase letters, numbers, and special characters. It should not contain dictionary words, personal information, keyboard patterns (like "qwerty"), or sequential characters (like "1234"). The strongest passwords are random or use a passphrase of unrelated words.
Crack time depends on password length, complexity, and the attacker's resources. Our tool estimates crack time assuming 10 billion guesses per second (a realistic rate for modern GPU-based attacks). A short, simple password like "abc123" can be cracked instantly, while a 16-character random password with mixed character types could take millions of years.
Yes. This tool runs 100% in your browser — your password is never sent to any server, stored, or transmitted over the internet. All analysis happens locally using JavaScript on your device. You can verify this by disconnecting from the internet and using the tool — it works completely offline.
The most commonly used (and most dangerous) passwords include "123456", "password", "qwerty", "iloveyou", "admin", "welcome", and "letmein". Our tool checks your password against a database of the top 200 most common passwords, including leet-speak variations like "p@ssw0rd". If your password is on this list, change it immediately.
Absolutely. A password manager generates, stores, and auto-fills unique, strong passwords for every account. This eliminates the biggest security risk — reusing the same password across multiple sites. Popular, trusted options include 1Password, Bitwarden, and Dashlane. Using a password manager with a strong master password is the single best thing you can do for your online security.
Modern security guidance (from NIST and other experts) no longer recommends changing passwords on a fixed schedule. Instead, change your password immediately if: (1) you suspect it's been compromised, (2) it appears in a data breach (check haveibeenpwned.com), (3) you shared it with someone, or (4) it's weak by current standards. Using a unique, strong password for each account is more important than frequent changes.
A brute force attack is when an attacker systematically tries every possible password combination until finding the correct one. Modern GPUs can test billions of combinations per second. This is why password length matters so much — each additional character exponentially increases the number of possible combinations. A 6-character password has about 2 billion combinations; a 12-character password has over 3 sextillion.
Yes, in most cases. A passphrase like "correct-horse-battery-staple" is both longer and easier to remember than a complex short password like "X#9kL!". The key is using 4+ random, unrelated words (not a famous quote or song lyric). Passphrases get their strength from length rather than complexity, making them an excellent choice for master passwords and accounts you type frequently.
Hackers use sophisticated tools that check common patterns first: dictionary words, keyboard walks ("qwerty", "asdfgh"), sequential numbers ("123456"), repeated characters ("aaaaaa"), leet-speak substitutions ("p@ssw0rd"), dates (birthdays, years), and common appended numbers ("password1"). Our checker detects all of these patterns and warns you if your password is vulnerable.
Two-factor authentication (2FA) adds a second layer of security beyond your password. Even if an attacker cracks your password, they can't access your account without the second factor — typically a code from an authenticator app, SMS, or a hardware security key. Enable 2FA on every account that supports it, especially email, banking, and social media. Authenticator apps (like Google Authenticator or Authy) are more secure than SMS-based 2FA.
Yes! Click the "Generate Strong Password" button to instantly create a cryptographically random password. Generated passwords use a mix of uppercase letters, lowercase letters, numbers, and special characters, and are designed to score in the "Strong" range. The password is generated entirely in your browser using the Web Crypto API — it's never sent to a server.