Password Generator
Adjust the inputs below. Results update as you type.
How it works
Password strength grows exponentially with length. An 8-character password with 94 printable ASCII characters has 94⁸ ≈ 6 quadrillion combinations—crackable in hours with modern GPUs. A 16-character random password has 94¹⁶ combinations—effectively uncrackable. Use a password manager to store unique passwords for every site. Passphrases (4–5 random words) are memorable and strong.
Input guidance
- Confirm date/time/unit settings before comparing outputs.
- If a task has optional fields, run both with and without them to understand impact.
- Save scenario variants when making practical decisions.
The formula
Password strength grows with length and character variety. The number of possible passwords is (character set size)^length, so entropy ≈ length × log₂(set size).
Worked example
A 12-character password using 94 printable symbols has about 12 × 6.55 ≈ 79 bits of entropy — extremely hard to brute-force.
More examples to test
- Quick-pass example: run default assumptions for a first estimate.
- Refined example: update one assumption at a time to isolate impact.
How to interpret results
Use outputs as operational estimates and pair them with local constraints, business rules, or provider requirements.
When this can be inaccurate
Utilities can miss local policy details, special-case rules, and environment-specific constraints.
Change history
- July 2026: Published local password generator with entropy and storage notes.
Site-wide corrections also appear on the corrections log.
Never forget a password again
Password manager — stores and auto-fills your passwords securely.
Frequently asked questions
What makes a strong password?+
Length above all, plus a mix of uppercase, lowercase, numbers, and symbols. A long random passphrase beats a short complex one.
Are generated passwords safe to use?+
A good generator uses randomness so the result is unpredictable. Store it in a password manager rather than reusing it across sites.
How long should a password be?+
At least 12–16 characters for important accounts. Each extra character multiplies the number of guesses an attacker would need.
Why are outputs slightly different from another tool?+
Different tools can use different rounding rules, default assumptions, and treatment of edge cases.
How can I improve estimate reliability?+
Use verified inputs from real records and re-run calculations after major assumption changes.
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