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Security Utility

Password Generator

Choose length and character types to generate a hard-to-guess random password. The password is generated in your browser with strength, entropy, and character set details.

Random Passwords Generate passwords that match your selected rules using the browser secure random API.
Strength and Entropy Review estimated password strength and entropy based on length and character pool.
Browser Processing Generated passwords are processed in the current browser and are not stored on the server.
GENERATE

Password Settings

Choose password length and character types, then generate a new password.

Ready
16

Choose a long password within the site's accepted limits and use a different value for each account.

Character types

REVIEW

Password Review

Review estimates for the selected length and character pool. Generate a new password after changing the options.

Length

16

Character set

-

Strength

Ready

Estimated entropy

-
Choose options and the generated password details will appear here.
Practical guide

Generate a unique password and understand the strength estimate

Choose the length and permitted character groups, then generate a new value for that account. The strength meter describes the selected character pool and length; it is not a certificate of account security or a measured time to crack.

Prepared & reviewed by
win-j
Last reviewed
2026-09-30

Who this helps

  • People creating different passwords for different accounts.
  • People matching a site's length and character restrictions.

When to use this tool

  • Generate a 16-character password with selected uppercase, lowercase, digit and symbol groups.
  • Exclude visually similar characters when a password needs to be read manually.

From input to a checked result

  1. 1

    Check the destination's accepted length and symbols. This tool supports lengths from 8 to 64.

  2. 2

    Choose the permitted groups and optionally exclude O, 0, o, I, l and 1.

  3. 3

    Generate a new result after setting the options; each selected group is represented.

  4. 4

    Save the generated value in a trusted password manager and verify that the destination accepts it.

  5. 5

    Use a different value for each account and enable additional account protection where available.

Example 1

A site's composition requirement

Input
Length 16; uppercase, lowercase, digits and symbols
Result
A new 16-character result containing at least one character from each selected group.

No fixed sample password is supplied for reuse. A site's accepted symbol list may differ from this tool's fixed symbol pool.

Example 2

Read a value aloud

Input
Length 20; letters and digits; exclude similar characters enabled
Result
20 characters without O, 0, o, I, l or 1.

Excluding characters makes the pool smaller. Use the generated result for one purpose rather than reusing it across accounts.

How it works

Character selection uses crypto.getRandomValues with rejection sampling to avoid modulo bias. The tool first chooses one character from each selected group, fills the remaining positions from the combined pool and shuffles them. The displayed estimate is length × log2(pool size), rounded for display.

Limitations

  • The entropy formula assumes independent, uniform choices. Mandatory group inclusion changes the distribution, so the displayed value is an upper estimate, not the exact entropy of this generator.
  • Symbols come from a fixed set; you cannot specify a custom allowed-symbol list.
  • A strong generated password does not protect against phishing, a compromised device or password reuse.
  • Clipboard history and synchronization can retain copied passwords outside this page.
Your data

Generation happens in the browser, and this tool does not send or store the generated value on the win-j server. Resetting the page does not clear your operating system's clipboard history.

Related tools

  • QR Code Generator

    Share a separate guest Wi-Fi password only with intended recipients; the QR contains readable credentials.

Frequently asked questions

Can I reuse a result if its strength is high?

No. A password exposed at one service can be tried at another regardless of the original strength estimate.

Is the displayed entropy exact?

No. It is a pool-and-length estimate. The required character groups and generation method mean it is not the exact entropy of the output distribution.

What if the site rejects some symbols?

This tool does not let you edit the symbol pool. Choose compatible groups and a suitable length, or use a generator with a custom alphabet if the site requires particular symbols.

Does Reset erase the copied password?

It clears the result on this page, not the system clipboard or its history. Manage those separately on your device.