Password Strength Checker – Is Your Password Strong Enough?
Test your password strength in real time. See a visual meter, detailed criteria checklist, and estimated brute-force crack time — everything runs locally in your browser, so your password is never transmitted or stored.
Enter Your Password
Brute force at 10 billion guesses/sec
Criteria Checklist
- At least 8 characters
- At least 12 characters
- At least 16 characters
- Uppercase letters (A-Z)
- Lowercase letters (a-z)
- Numbers (0-9)
- Symbols (!@#$...)
- Not a common password
Why Use Tools Oasis Password Strength Checker?
Tools Oasis analyzes your password entirely in your browser — nothing is ever sent to a server. Get instant feedback with a visual strength meter, detailed criteria breakdown, and a realistic brute-force crack time estimate.
Entropy by password type
Entropy measures how hard a password is to guess. This tool calculates it using NIST-aligned guidelines.
Web Crypto API
Uses crypto.getRandomValues() — cryptographically secure, not the predictable Math.random().
Zero Transmission
Values are generated client-side and never sent, logged, or stored anywhere.
No Limits
Generate as many results as you need, for free, with no rate limits.
Generating strong passwords is the first step. A password manager stores them all securely so you never have to remember them — one master password for everything.
Try NordPass — Free Password ManagerFrequently Asked Questions
01 Is my password sent to a server when I check it?
No. Tools Oasis performs all password analysis entirely in your browser using JavaScript. Your password is never transmitted, stored, or logged anywhere.
02 How is the crack time calculated?
The tool estimates crack time based on brute-force attacks at 10 billion guesses per second. It calculates the total keyspace (charset size raised to the power of password length) and divides by the guess rate.
03 What makes a password 'Very Strong'?
A 'Very Strong' password is typically 16+ characters long and includes a mix of uppercase letters, lowercase letters, numbers, and symbols. It should also not appear in common password lists.
04 Does this tool check if my password has been leaked?
This tool checks against a built-in list of the top 1,000 most common passwords. For a full breach check, you can use services like Have I Been Pwned.
05 How long should my password be?
Security experts recommend at least 12 characters, but 16 or more is ideal. Each additional character exponentially increases the time required to brute-force the password.
More Questions About Password Strength
01 Is my password sent to any server?
No. All analysis happens entirely in your browser using JavaScript. Your password is never transmitted, stored, or logged anywhere. You can even disconnect from the internet and the tool will still work.
02 How is the estimated crack time calculated?
The tool calculates the total number of possible combinations (character set size raised to the power of password length) and divides by 10 billion guesses per second — a realistic rate for modern GPU-based cracking rigs.
03 What does "common password" mean?
The tool checks your password against a built-in list of the top 1,000 most frequently used passwords (like "123456", "password", "qwerty"). Attackers try these first, so using one makes your account trivially easy to breach.
04 What makes a password "Very Strong"?
A "Very Strong" password typically has 16 or more characters and includes uppercase letters, lowercase letters, numbers, and symbols. It also must not appear in common password lists. Such passwords would take billions of years to crack by brute force.
05 Should I use a passphrase instead of a password?
Yes, passphrases (e.g., "correct-horse-battery-staple") can be both stronger and easier to remember than short complex passwords. The key is length — a 4-word passphrase with 25+ characters is extremely difficult to crack even without symbols.