Password Strength Checker - Test Password Security Online
Test how strong your password is and get tips to improve it.
100% local — your password is never sent anywhere.
What is a Password Strength Checker?
A password strength checker is a free online tool that analyses a password and estimates how resistant it is to guessing and brute-force attacks. It measures entropy in bits from the character set and length, detects weak patterns, and estimates how long an attacker would take to crack it — all locally in your browser.
Why Use a Password Strength Checker?
It is easy to overestimate how strong a password is. A strength checker gives you an objective measure, flags dictionary words and common patterns, and offers concrete tips so you can build passwords that actually hold up.
- Measure password entropy in bits
- See an estimated offline crack time
- Detect common words, sequences, and repeats
- Get a clear Very Weak to Very Strong rating
- Receive actionable tips to improve
- 100% local — your password is never sent anywhere
Common Password Strength Checker Use Cases
Personal Security
Check that your passwords are strong before you use them.
Security Education
Learn what makes a password strong or weak.
Policy Compliance
Verify passwords meet organisational standards.
Security Audits
Audit credential quality during reviews.
App Development
Understand entropy when building password rules.
Family Safety
Help family members pick safer passwords.
Password Strength Checker for Everyone
Our password strength checker is designed for:
- Everyday internet users
- Security professionals
- Software developers
- IT administrators
- Compliance and audit teams
- Educators and trainers
- Privacy-conscious users
- Anyone improving their passwords
🎥 Video Guide
❓ FAQs
What is a password strength checker?
It analyses a password and estimates how resistant it is to guessing and brute-force attacks, based on its length, character variety, and patterns.
How is password strength measured?
This tool estimates entropy (in bits) from the character set and length, then maps it to a strength rating and an approximate offline crack time.
Is it safe to type my real password here?
Yes. The check runs entirely in your browser. Your password is never sent to a server, logged, or stored anywhere.
What makes a password strong?
Length is the biggest factor, followed by using a mix of uppercase, lowercase, numbers, and symbols, and avoiding dictionary words and common patterns.
What is password entropy?
Entropy measures unpredictability in bits. Each extra bit doubles the number of guesses an attacker needs, so higher entropy means a stronger password.
Why is my long password still rated weak?
Common words, repeated characters, keyboard patterns like 'qwerty', and simple sequences reduce real strength even when a password is long.
Is this tool free?
Yes. It is completely free with no registration required.
Which browsers support this tool?
It works on Chrome, Firefox, Safari, Edge, and all modern browsers.