Password Strength Checkers vs. Password Generators: Which Should You Use?

Choosing between password strength checkers and password generators depends on your specific needs. This guide explains what each tool does, when to use them, and how they work together to secure your accounts.

What Is a Password Strength Checker?

A password strength checker evaluates passwords you create. It analyzes:

  • Length: Number of characters
  • Complexity: Mix of uppercase, lowercase, numbers, and special characters
  • Common patterns: Sequences like "123456" or "qwerty"
  • Dictionary words: Recognizable words or phrases
  • Personal information: Names, birthdays, or predictable substitutions

When to Use a Strength Checker

Use a password strength checker when you need to:

  • Create a master password for your password manager
  • Build a memorable password for accounts where you can't paste
  • Verify that an existing password meets security requirements
  • Learn what makes passwords secure

Strengths of Password Checkers

  • Provide immediate feedback on password quality
  • Help you learn password security principles
  • Allow you to create memorable passwords that still meet security standards
  • Free and widely available

Limitations of Password Checkers

  • Different checkers use different algorithms, producing inconsistent results
  • Cannot detect if your password appears in breach databases (unless integrated with one)
  • May give false confidence for predictable patterns
  • Still rely on human creativity, which tends toward predictable patterns

What Is a Password Generator?

A password generator (or password creator) creates random passwords using algorithms designed to maximize unpredictability. Quality generators:

  • Use cryptographically secure randomization
  • Allow customization of length and character types
  • Produce passwords that resist cracking attempts
  • Generate unique passwords instantly

When to Use a Password Generator

Use a password generator for:

  • Any account stored in a password manager
  • Financial accounts and email
  • Social media and shopping sites
  • Work applications and subscriptions
  • Any account where maximum security matters

Strengths of Password Generators

  • Create truly random passwords without human bias
  • Eliminate predictable patterns attackers exploit
  • Save time—no need to invent passwords
  • Consistently produce high-security passwords

Limitations of Password Generators

  • Generated passwords are impossible to memorize (requires a password manager)
  • May occasionally conflict with specific site password requirements
  • Depend on the quality of the random number generator used

The Practical Answer: Use Both

You need both tools because they solve different problems:

Use generators for 99% of your passwords. Store them in a password manager. This gives you maximum security without memorization burden.

Use checkers for the 1% you must remember. Specifically your password manager's master password and any account that blocks pasting.

Your Complete Password Strategy

Step 1: Get a Password Manager

Choose a reputable option:

  • Bitwarden (open source)
  • 1Password
  • LastPass
  • KeePass (offline option)

This is non-negotiable for modern password security.

Step 2: Create One Strong Master Password

Your master password must be both secure and memorable. Use the passphrase method:

  1. Choose 4-6 random, unrelated words
  2. Add numbers and symbols
  3. Verify with a strength checker

Example: Cobalt-Harvest-Telescope-592!

This is the only password you'll memorize.

Step 3: Generate All Other Passwords

Configure your password manager's generator:

  • Minimum 16 characters (20+ is better)
  • Include all character types
  • Generate a unique password for every account

Never reuse passwords across sites.

Step 4: Enable Two-Factor Authentication

Add 2FA to critical accounts:

  • Password manager
  • Email
  • Financial accounts
  • Work accounts

Use authenticator apps (Google Authenticator, Authy) rather than SMS when possible.

Step 5: Audit Regularly

Every 3-6 months:

  • Use your password manager's security audit feature
  • Check for weak or reused passwords
  • Replace any that fail strength requirements
  • Verify against breach databases

Common Questions Answered

Q: How long should passwords be?

A: Minimum 12 characters for basic accounts, 16+ for important accounts. Length matters more than complexity—a 20-character password with only lowercase letters is harder to crack than an 8-character password with mixed characters.

Q: Should I change passwords regularly?

A: No, unless there's evidence of compromise. Frequent changes lead to weaker, more predictable passwords. Focus on using strong, unique passwords from the start.

Q: Can I write down generated passwords?

A: If stored securely offline (locked safe), written passwords can be acceptable as backup. Physical security at home often exceeds digital security of weak passwords vulnerable to online attacks.

Q: What if a website doesn't allow pasting?

A: Create a strong memorable password using the passphrase method and verify it with a strength checker. This is one of the rare cases where generators aren't practical.

Q: Are all password generators equal?

A: No. Use generators from reputable password managers or security companies. Avoid random online generators, as you can't verify their randomness quality or if they're logging passwords.

Q: Which password strength checker should I use?

A: Use checkers from established security organizations:

  • Have I Been Pwned's password checker
  • Your password manager's built-in checker
  • zxcvbn (open-source library used by many services)

Technical Considerations

Password Entropy

Entropy measures password unpredictability. Higher entropy = harder to crack:

  • 8 random lowercase letters: ~37 bits of entropy
  • 8 mixed characters: ~52 bits
  • 16 mixed characters: ~95 bits
  • 6-word passphrase: ~77 bits

Aim for minimum 60 bits of entropy for important accounts.

Common Attack Methods

Understanding threats helps explain why generated passwords work better:

  • Dictionary attacks: Try common words (defeated by random generation)
  • Brute force: Try all combinations (defeated by length)
  • Credential stuffing: Reuse leaked passwords (defeated by unique passwords)
  • Social engineering: Guess personal information (defeated by randomness)

Character Requirements

Some sites enforce specific requirements like "must include a symbol." Configure your generator to match:

Minimum length: 16
Include uppercase: Yes
Include numbers: Yes
Include symbols: Yes
Exclude ambiguous characters: Optional (preference)

Implementation Checklist

  1. Install a password manager
  2. Create a strong master password using passphrases
  3. Verify master password with a strength checker
  4. Generate new passwords for critical accounts (email, banking)
  5. Gradually replace old passwords with generated ones
  6. Enable 2FA on all accounts that support it
  7. Set a reminder for quarterly security audits
  8. Never reuse passwords across different sites

Conclusion

Password strength checkers evaluate passwords you create. Password generators create passwords for you. Use generators for virtually everything, stored in a password manager. Use checkers only for the master password you must memorize.

The era of memorizing dozens of passwords is over. Modern security means using random generated passwords for maximum protection, with the convenience of a password manager handling the complexity for you.