How secure is a 4-digit PIN?

A 4-digit PIN has only 10,000 possible combinations (~13 bits of entropy). This is weak by password standards but acceptable when combined with lockout policies. Without lockouts, an attacker could crack it in seconds. For online accounts without lockouts, use full passwords instead.

Is 6-digit better than 4-digit?

Yes, significantly. A 6-digit PIN has 1,000,000 combinations versus 10,000—100 times harder to guess. This is why Apple switched iOS from 4 to 6 digits by default. Use 6+ digits whenever the system allows it.

Should I use my birthday as a PIN?

Never. Birthdays, addresses, and phone numbers are easily guessable from social media. Studies show attackers try birth years and dates first. Always use randomly generated PINs with no personal significance.

What PINs should I avoid?

Avoid common PINs like 1234, 1111, 0000, and any patterns like 1212 or 7777. Also avoid sequences (1234, 4321), repeated digits (5555), and keyboard patterns. Our generator automatically avoids these when pattern avoidance is enabled.

Secure PIN Generator - Random 4-8 Digit PINs

Generate a Secure PIN — Random 4–8 Digit PIN Creator

Generate cryptographically secure random PINs using the Web Crypto API. Create 4-digit, 6-digit, or custom length PINs for banking, phones, and security systems. Automatic pattern avoidance keeps your PIN unpredictable. For stronger protection, consider a full password or passphrase.

The Science of PIN Security

A PIN (Personal Identification Number) trades security for convenience. With only 10 possible digits versus 95+ printable characters, PINs have inherently low entropy. Understanding when this tradeoff is acceptable—and when it's dangerous—is crucial for protecting your accounts.

Why Lockouts Matter

A 4-digit PIN has only 10,000 possible combinations. Without protection, an attacker could try all of them in under a second. But with a 3-attempt lockout policy, the odds shift dramatically: an attacker has only a 0.03% chance of guessing correctly before being locked out. This is why PINs are acceptable for ATMs and phones—not because they're strong, but because the system limits attempts.

Human PIN Biases

Research on leaked PIN databases reveals fascinating patterns. People overwhelmingly choose years (1984, 2024), dates (0315 for March 15), and patterns (1234, 1111). Numbers starting with 19 are vastly overrepresented—birth years. Our generator eliminates these biases by using true cryptographic randomness.

The Math of PIN Length

Each digit you add multiplies possible combinations by 10. This exponential growth makes longer PINs dramatically more secure:

4 digits: 10⁴ = 10,000 combinations (~13 bits entropy)
6 digits: 10⁶ = 1,000,000 combinations (~20 bits entropy)
8 digits: 10⁸ = 100,000,000 combinations (~27 bits entropy)

For comparison, a random 8-character password using all character types has ~52 bits of entropy—nearly double an 8-digit PIN. When lockouts aren't guaranteed, always use full passwords.

Generate a Secure PIN — Random 4–8 Digit PIN Creator

PINs to Avoid

PIN Length Security Comparison

4-Digit PIN

6-Digit PIN

8-Digit PIN

When to Use PINs vs Passwords

✓ PINs Work Well For

✗ Never Use PINs For

Frequently Asked Questions