Password Strength Checker – Test Your Password Security
Check your password strength online with our free, privacy-first password strength checker. Analyzes entropy, crack time, and 9 security criteria—your password never leaves your browser.
Runs in your browser
WebAssembly, no server
No signup required
Open and use instantly
Files stay private
Nothing leaves your device
How It Works
Type or paste your password into the input field
The strength meter updates in real time as you type
Read the analysis: strength rating, estimated crack time, and detected issues
Key Features
- Real-time strength score (Very Weak to Very Strong)
- Estimated time to crack by brute force
- Character type analysis (uppercase, lowercase, numbers, symbols)
- Common password detection
- Keyboard pattern detection (qwerty, 12345)
- Repeated character detection
- Specific improvement suggestions
- Show/hide password toggle
- 100% private — password never leaves browser
- No sign-up required
- Free with no limits
- Mobile-friendly
About This Tool
Our Password Strength Checker analyzes your password in real time and tells you exactly how secure it is — and how to make it stronger.
What Gets Analyzed
- Length: longer passwords are exponentially harder to crack
- Character variety: uppercase, lowercase, numbers, symbols
- Common patterns: dictionary words, keyboard walks (qwerty), repeated characters
- Common passwords: checked against the most frequently used password lists
- Entropy: mathematical measure of unpredictability in bits
Strength Levels
- Very Weak: cracked in milliseconds
- Weak: cracked in minutes to hours
- Fair: cracked in days to months
- Strong: cracked in years
- Very Strong: effectively uncrackable with modern hardware
Best Practices for Strong Passwords
- Use at least 12 characters (16+ for sensitive accounts)
- Mix uppercase, lowercase, numbers, and symbols
- Avoid real words, names, dates, or keyboard patterns
- Use a password manager to generate and store unique passwords
- Never reuse passwords across multiple sites
Privacy Guarantee
Your password is analyzed entirely in your browser. It is never sent to any server, logged, or stored. The tool cannot see what you type.
Frequently Asked Questions
No. All analysis runs in your browser using JavaScript. Your password is never transmitted or stored anywhere.
Length is the most important factor. Using 16+ characters with a mix of uppercase, lowercase, numbers, and symbols creates a very strong password.
Entropy measures how unpredictable a password is in bits. Higher entropy means harder to crack. A 128-bit entropy password is considered uncrackable.
The tool estimates crack time based on modern hardware brute-force rates. A strong password should show 'centuries' or more.
No. It contains a common dictionary word and predictable pattern. It would be cracked in under a second by modern tools.
At least 12 characters for general accounts. 16+ characters for financial or sensitive accounts.
Yes — password managers generate, store, and auto-fill unique strong passwords for every site, eliminating the need to memorize them.
Related Tools
Free Password Generator Online - Generate Strong & Secure Passwords Instantly
Generate strong, random, and secure passwords online with our free Password Generator. Customize password length and character types to protect your accounts from hacking and unauthorized access. All password creation is done instantly in your browser for maximum privacy—no data is ever stored or sent to a server.
Hash Generator - MD5, SHA, BLAKE2
Generate cryptographic hashes online instantly with support for MD5, SHA-1, SHA-256, SHA-512, and BLAKE2. Hash text or files for security, integrity checks, or development—no data leaves your device. Fast, secure, and free.
Base64 Encoder & Decoder
Easily encode text or files to Base64 and decode Base64 strings online with our free, secure Base64 Encoder & Decoder. Perfect for developers handling API data, debugging web responses, or preparing encoded content. All processing is local and private—no uploads or data storage.
JWT Decoder
Decode and inspect JSON Web Tokens (JWT) securely online in your browser. Instantly view JWT headers and payloads for debugging, development, or learning—no uploads, no risk of data exposure. 100% private and free.
Free UUID Generator Online - Generate UUID v4, v1, v7 Instantly
Create random UUID version 4 (v4) identifiers online instantly with our UUID Generator. Ideal for developers, database administrators, and API designers who need globally unique IDs without collisions. Fast, secure, and browser-based—no signup or installation required.
Free Case Converter Online - Convert Text to Uppercase, Lowercase, Title Case
Instantly convert text between UPPERCASE, lowercase, Title Case, and more online with our Case Converter & Text Formatter. Clean and format your content for publishing, coding, or social media—fast, secure, and browser-based with no data saved.