How to Generate a Secure Password
Set your desired password length using the slider (8–128 characters), then select which character sets to include: uppercase letters, lowercase letters, numbers, and symbols. Click 'Generate' to create a cryptographically secure password using your browser's Web Crypto API. Use 'Copy' to copy it to your clipboard, or enable bulk mode to generate multiple passwords at once.
Why Use UtilDaily Password Generator?
- Cryptographically secure — uses crypto.getRandomValues(), not Math.random()
- Entropy-based strength meter shows exactly how strong your password is in bits
- Bulk generation mode creates 5, 10, or 20 passwords at once for batch provisioning
- Full character set control — customize uppercase, lowercase, numbers, and symbols
- 100% client-side — your passwords are never transmitted to any server
- Works offline after first page load — no internet connection needed to generate
Frequently Asked Questions
What makes a password cryptographically secure?
A cryptographically secure password uses a cryptographically secure pseudo-random number generator (CSPRNG). This generator uses crypto.getRandomValues(), which is backed by the operating system's entropy source (like hardware noise on modern devices). Unlike Math.random(), which is predictable, crypto.getRandomValues() produces outputs that are computationally infeasible to predict or reproduce.
What is password entropy and how is it calculated?
Password entropy measures the unpredictability of a password in bits. It is calculated as: entropy = length x log2(charset_size). For example, a 16-character password using all character sets (95 printable ASCII characters) has 16 x log2(95) = approximately 104.7 bits of entropy. Security experts generally recommend at least 80 bits for high-security use cases.
How long should my password be?
NIST SP 800-63B recommends at least 8 characters as a minimum, but modern best practice is 16+ characters for general accounts and 20+ for high-value accounts (banking, email). Length has the greatest impact on entropy — adding characters is more effective than adding character types. A 20-character lowercase-only password is stronger than an 8-character password with all character types.
Is my generated password saved anywhere?
No. Passwords are generated entirely in your browser's memory using JavaScript. They are never sent to UtilDaily's servers, stored in cookies, or written to localStorage. You can verify this by opening DevTools Network tab — no network requests occur when generating passwords. Once you close the tab, the passwords are gone.
By UtilDaily · Updated \u2014 free, privacy-first browser tools. No sign-up, no data collection.