Password Generator
The Password Generator creates unpredictable strong passwords instantly using cryptographically secure random numbers. Supports 4-128 character length, uppercase/lowercase/numbers/symbols combinations, and bulk generation. All processing happens in-browser with no external transmission.
What You Can Do
The Password Generator instantly creates strong, unpredictable random passwords. Freely customize length and character types (uppercase, lowercase, numbers, symbols) to create unique secure passwords for each service. All processing happens in your browser, so your passwords are never transmitted externally.
- ✅ Length Control: Freely set from 4 to 128 characters
- ✅ Character Selection: Customize combinations of uppercase, lowercase, numbers, and symbols
- ✅ Bulk Generation: Generate multiple passwords at once with one-click copy
Generate multiple passwords at once and copy with one click. Recommended for use with password managers.
🔐 Generation Settings
📋 Generated Passwords
Generated passwords will appear here
💼 Use Cases
- Creating new accounts - Generate strong passwords that are hard to guess
- Regular password changes - Create complex passwords that meet security policies
- Using different passwords per service - Prevent password reuse with random generation
- When symbols are required - Select character types to meet requirements
- Prioritizing security over memorability - Use with password managers
How to Use
📌 Basic Usage
Simply select password length and character types, then click "Generate Password" to create secure random passwords.
💡 Recommended Settings
- Length: Minimum 12 characters recommended (16+ characters is more secure)
- Character types: Include all - uppercase, lowercase, numbers, and symbols
- Duplicates: Allowing duplicates creates passwords that are harder to guess
⚙️ Options
- Generation count: Generate multiple password candidates at once
- Duplicate characters: Control whether the same character can be used multiple times
🔒 Security Tips
- Use different passwords for each service
- Change passwords regularly
- Save generated passwords in a password manager (recommended)
- Avoid easily guessed information like birthdays or names
🔬 How Password Strength Works
Entropy (Strength Indicator)
Password strength is measured by <strong>"entropy (information content)"</strong>, expressed in bits. For example, a 16-character password containing uppercase, lowercase, numbers, and symbols has approximately <strong>104 bits</strong> of entropy, which would take even modern supercomputers <strong>thousands of years</strong> to crack.
Formula: Entropy = log₂(character types^password length)
Example: 16 characters, 94 character types → log₂(94¹⁶) ≈ 104 bits
Attack Methods and Countermeasures
- Dictionary attack: Tries common words and known password lists. Completely prevented by random generation
- Brute force: Tries all combinations. 12+ characters makes this virtually impossible (would take tens of thousands of years at 10 billion attempts per second)
- Rainbow table: Uses pre-computed hashes. Prevented by using different passwords for each service
NIST Recommended Standards (2024)
The National Institute of Standards and Technology (NIST) recommends a minimum password length of 8+ characters, with 12-16 characters being ideal. This tool's default setting (16 characters) meets NIST standards. NIST also states that "regular password changes are unnecessary," recommending changes only when a data breach occurs.
What is the Password Generator?
The Password Generator is a free online tool that instantly creates secure random passwords. It supports customization of length and character types.
Who is this for?
Anyone creating new accounts who needs strong passwords, people wanting to stop reusing passwords, administrators generating multiple passwords at once, and those following security policies for password creation.
Key Features
- Customizable character types: uppercase, lowercase, numbers, and symbols
- Bulk generation of multiple passwords at once
- Built-in password strength indicator
- Completely free with no registration required
- All processing is done in your browser - no data is sent to any server
FAQ
They use a cryptographically secure random number generator (Crypto.getRandomValues) to produce unpredictable passwords. A 16-character password with uppercase, lowercase, numbers, and symbols has approximately 104 bits of entropy, which would take modern supercomputers thousands of years to crack.
Yes, you can bulk generate up to 50 passwords at once. Set the generation count and click "Generate Password." Generated passwords can be copied individually or all at once using the "Copy All" button.
Strength is determined based on password length and character types used. Passwords with 12+ characters including uppercase, lowercase, numbers, and symbols are rated "Strong." Partially meeting these criteria results in "Medium," while short passwords or those with few character types are rated "Weak."
No, all processing is done in your browser. Your input data is never sent to a server.
It's completely free with no usage limits. No user registration is required.
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