Password Strength Checker

Analyze your password's security in real-time. We calculate entropy, estimate crack time, and provide actionable security feedback.

100% Secure. Processed locally.
Strength Meter Waiting...
Entropy Score
0 bits
Length
0 chars

Enter a password to see analysis...

Estimated Crack Time

Brute Force (Online)
...
100 attempts/sec
Brute Force (Offline)
...
10B attempts/sec

Character Composition

Uppercase
Lowercase
Numbers
Symbols

How to analyze your security

1

Input Password

Type or paste the password you want to test. Our tool analyzes it instantly as you type.

2

Check Metrics

Review entropy bits, character composition, and estimated crack times for different scenarios.

3

Apply Tips

Follow the dynamic security suggestions to transform a weak password into an unbreakable one.

Understanding Password Entropy

Entropy is a measure of randomness or unpredictability. In cryptography, it tells us how many "guesses" a computer would need to make to find your password. The higher the entropy (measured in bits), the more secure your password is.

Standard
80+ bits is Secure
Warning
Below 40 bits is Weak

Built with a security-first mindset

Zero-Server Analysis

Unlike many checkers, we never transmit your password to any server. All calculations happen locally using standard JavaScript, ensuring your secret stays on your machine.

Brute-Force Simulator

We simulate both online (rate-limited) and offline (massive GPU cluster) attack scenarios to give you a realistic view of how long your password would last against modern hardware.

Pattern Detection

Our logic detects common weaknesses such as keyboard patterns (qwerty), sequential characters (abc), repeated characters (aaa), and length-based vulnerabilities.

Dynamic Suggestions

Don't just know your password is weak—know how to fix it. We provide targeted advice based on your input's specific flaws to help you improve security.

Expert Security Q&A

Is it safe to type my password here?
Yes. This tool is client-side only. Your password never leaves your browser, and no data is sent to our servers. For maximum safety, you can even use this tool while offline.
How is crack time calculated?
We use your password's entropy to estimate how many attempts it would take to guess. We then divide that by typical attack speeds: 100 attempts per second for online attacks (due to rate limiting) and 10 billion per second for offline brute-force attacks using modern hardware.
Should I use a password manager?
Absolutely. A password manager allows you to use unique, complex passwords for every account without having to memorize them. This is the single best thing you can do for your online security.