Password Strength Checker
Test your password security and get instant feedback on how to improve it.
Password Strength Features
Comprehensive password security analysis.
Visual strength meter from Very Weak to Very Strong.
Shows password entropy bits for technical insight.
Detects common patterns, keyboard walks, and repeats.
Key Takeaways
- The checker runs entirely in JavaScript in your browser as you type, so the password stays on your device and is never sent to a server.
- The score combines concrete signals - length tiers at 8, 12, and 16 characters plus one point per character type - while matching a built-in common-password list or simple patterns like 123 or repeats subtracts up to 3 points.
- The displayed crack time is only a rough comparison estimate based on charset size and length at one billion guesses per second, not a guarantee, since real attack speed depends on a site's hashing method.
- Aim for Strong (12 or more mixed characters with no common pattern) for most accounts and 16 plus characters for anything protecting money or identity; a long password can still score low if it is built from repeats or sequences.
How to Check Your Password Strength
Type a password into the field
Enter the password you want to test in the input box. The check runs the moment you type, so there is no submit button to press. Everything is analyzed by JavaScript in your browser, and the password stays on your device.
Read the meter and requirement checks
Watch the colored strength meter move from Very Weak to Very Strong and read the matching label. Below it, six checks light up: at least 8 characters, an uppercase letter, a lowercase letter, a number, a special character, and whether it matches a known common password.
Review the crack time and improve
The tool prints an estimated crack time based on the character set you used and the length. Use the Show button to reveal the text while editing, then add length and missing character types until the meter and crack time both improve.
What the Checker Measures
The score is built from a small set of concrete signals rather than a single rule. Each signal below either adds to the score or, in the case of a common password, subtracts from it. The result is mapped to one of five strength levels.
| Signal | How it is tested | Effect on score |
|---|---|---|
| Length 8+ | Password is at least 8 characters | Adds 1 point |
| Length 12+ and 16+ | Longer passwords pass extra length tiers | Adds 1 point at each tier |
| Character variety | Presence of uppercase, lowercase, numbers, and symbols | Adds 1 point per type used |
| Common password | Matched against a built-in list of weak passwords | Subtracts up to 3 points |
| Simple patterns | Repeated characters or sequences like 123 or abc | Treated as common and penalized |
| Crack time | Charset size raised to the length, at 1 billion guesses per second | Shown as an estimate, not scored |
Which Result Should You Aim For
Very Weak or Weak
Usually short passwords, a single character type, or a match against the common password list. The estimated crack time often reads as instant. Rewrite the password entirely before using it anywhere.
Fair
You have some variety and length but are missing a character type or are still on the short side. Acceptable for low-value logins only. Add length and a symbol to move up a level.
Strong
Twelve or more characters with a good mix of character types and no common pattern. Suitable for most accounts. Reach for 16 plus characters on anything that protects money or identity.
Very Strong
Long, mixes uppercase, lowercase, numbers, and symbols, and avoids known patterns. The crack time estimate climbs into years or beyond. Ideal for password managers, email, and primary accounts.
Common Problems and Fixes
The meter stays empty
The analysis runs only while the field has text. If the box is empty the meter, label, and crack time are cleared on purpose. Type at least one character and the checks will respond immediately.
A long password still scores low
Length alone is not enough if it matches the common list or is built from repeats or simple sequences such as aaaaaa or 123456. Those trigger the common penalty. Break the pattern by mixing unrelated characters and casing.
The crack time seems optimistic or harsh
The estimate assumes a fixed rate of one billion guesses per second and only counts the character classes you actually used. It is a rough guide for comparison, not a guarantee. Real attack speeds vary with the hashing method used by a site.
I cannot tell what I typed
The field is masked by default. Click the Show button to reveal the text while you edit, then click Hide to mask it again. The password stays on your device throughout and is not sent anywhere.
About Password Strength Checker
Check the strength of your password and get actionable tips to improve its security.
Frequently Asked Questions
Is this tool free to use?
Yes, this tool is completely free.
No account or registration is required.
You can use it as many times as you like.
Is my data private?
Browser-side workflows run locally.
Your data is never sent to any server.
We do not store, log, or share your input.
Does it work on mobile?
Yes, the tool is fully responsive.
It works on phones, tablets, and desktops.
No app download is needed.
Do I need to install anything?
No installation is required.
It runs entirely in your web browser.
Works on any modern browser without plugins.
Is there a file size limit?
There is no strict file size limit.
Very large inputs may be limited by browser memory.
For best performance, keep inputs under a few MB.
Can I use the output commercially?
Yes, there are no restrictions on usage.
The output belongs entirely to you.
Use it for personal or commercial projects freely.
What browsers are supported?
All modern browsers are supported.
This includes Chrome, Firefox, Safari, and Edge.
Keep your browser updated for best results.
How accurate is the result?
Results are highly accurate for standard inputs.
Edge cases may produce unexpected output.
Always review the output before using it in production.
Works in Chrome, Firefox, Safari, Edge, Opera, and other modern browsers on Windows, macOS, Linux, Android, and iOS. No software installation or sign-up required. All conversions run directly in your browser, so your files never leave your device and are never uploaded to a server. Free to use with no account needed.
Sources and References
Format and tool details on this page are based on the official specifications and documentation below.
- Digital Identity Guidelines (SP 800-63B)- NIST
- Password / authentication guidance- OWASP Cheat Sheet Series