Test password security instantly with our password strength checker. Run locally in your browser—no data stored, 100% private.
Enter a password to see its strength
100% Private: Your password is checked locally in your browser and never transmitted to our servers. No data storage or logs. Once you check your password's strength, you can create new secure passwords using our password generator.
While our tools help you create and check passwords, a professional password manager ensures all your passwords are automatically generated, stored securely, and filled in seamlessly across all your devices.
Trusted by millions of users worldwide
Real-time analysis that evaluates entropy, character diversity, and vulnerability patterns
Real-time password strength feedback as you type. Identify weak patterns, entropy score, and specific criteria. See exactly what your password needs to be strong.
100% client-side security analysis. Your passwords never leave your device. No transmission to servers, no data storage, no tracking. Pure local encryption.
Zero cost, no registration required, no hidden fees. Free password strength checking, forever. Plus try our free random password generator tool.
Your definitive resource for understanding how password strength checkers work, why length and entropy matter, and how to harden your online accounts with smart habits and the right tools.
A password strength checker is an online utility that evaluates the security of a password by analysing its length, complexity, and resistance to common attack techniques. Our password strength checker runs entirely in your browser, ensuring no data is ever transmitted or stored. The tool supplies a clear rating and actionable feedback, helping you choose passwords that are truly hard to crack.
Some services call themselves "password testers" and claim to simulate real-world attacks. In practice the terms are interchangeable, but the key is how the analysis is performed. A trustworthy tester operates locally, calculates entropy, and estimates crack time. Beware of sites that request your actual credentials – our tools are safe and private.
Security depends on two simple factors: unpredictability and length. A twelve-character password made of random letters, numbers and symbols is orders of magnitude stronger than a common word with a digit appended. To gauge where you stand, enter your candidate in our checker and review the detailed breakdown of entropy and estimated crack time.
Entropy measures the randomness of a password in bits. Each additional bit doubles the number of possible combinations. High entropy means an attacker must perform significantly more guesses to succeed. Our evaluation converts your password into an entropy score so you can compare lengths and character sets objectively.
While mixing character types helps, the single most important factor is the number of characters. Adding just one extra character increases the search space exponentially. A sixteen‑character random string is vastly stronger than an eight‑character password with symbols. When in doubt, make it longer.
Our tools check against known weak-password lists so you can see if your choice has already appeared in a breach.
Attackers often start with social engineering and phishing to obtain login details. Once they have a hashed password, they may run it through cracking software on powerful GPUs or cloud rigs. The only reliable defence is to make the hash expensive to compute by choosing a strong password and using services that apply proper hashing algorithms and salting.
Start by checking existing credentials with the strength checker. If the score is low, use our random password generator to produce a long, unpredictable passphrase. You can then plug the generated password back into the checker for validation.
Password managers store encrypted passwords and fill them automatically when you log in. They allow you to use unique, complex passwords without the burden of memorisation. Many also include built‑in generators and security audits. A good manager is an essential component of modern password hygiene.
Not all "checkers" are created equal. Scammers may collect passwords for malicious use. Our code executes entirely in your browser, meaning your input never leaves your device. Before using any online tool, review its privacy policy and inspect the source if possible. You can also run open‑source checkers locally to eliminate risk.
Scroll down to the dedicated FAQ section for quick answers to common questions about password strength, security tools and best practices.
Quick answers to help you understand password strength, security tools, and best practices.
A password strength checker evaluates how resistant a password is to hacking attempts by analysing length, complexity and entropy. Use it to gauge whether your chosen password meets security standards before setting or updating credentials.
Functionally they are similar; both assess your password against known attack methods. The distinction often lies in marketing. Always ensure the tester runs locally and does not upload your password.
Yes. Our application does all processing in your browser and never sends or stores any data. If you have any doubts, use a placeholder and compare the entropy score manually.
A properly implemented generator produces high-entropy, unpredictable strings that are virtually impossible to crack by brute force. Our random password generator uses cryptographically secure randomness.
Brute force tries every possible combination, while dictionary attacks start with common words and leaked passwords. Long, random passwords protect against both by vastly increasing the search space.
Each additional character multiplies the number of possible passwords. Adding one character is more effective than adding several types of symbols. Aim for length first, then variety.
Entropy quantifies how unpredictable a password is, measured in bits. Higher entropy means more possible combinations and a longer time required to guess the password.
No. Reusing passwords is a major risk because a breach on one service allows attackers to access your accounts elsewhere. Always use unique passwords.
Password managers generate, store, and auto-fill complex, unique passwords for every site, reducing the likelihood of reuse and weak choices. They are an effective tool for maintaining good password hygiene.
Besides brute force and dictionary attacks, hackers use phishing, keyloggers, social engineering, and exploiting poor hashing algorithms. Strong passwords, MFA, and security awareness are your best defences.
Yes, if it contains common patterns, dictionary words or has been leaked previously. Use a checker and avoid reused or predictable components.
Change them immediately after any suspected compromise. For most users, focusing on uniqueness and strength is more important than frequent rotation. High-value accounts may warrant more regular changes.
Immediately change your password on that service and any others where you've reused it. Enable multi-factor authentication and monitor for suspicious activity.
Estimates are theoretical averages based on current hardware capabilities and attack methodologies. They give a reasonable sense of relative strength but are not guarantees against every attacker.