Science Nov 29, 2025

What is "Entropy"? The Hidden Math Behind Your Password

We often hear "make your password strong," but what does "strong" actually mean mathematically? It’s not about how hard it is for a human to guess; it’s about how hard it is for a computer to calculate.

This measure of difficulty is called Information Entropy, measured in "bits".

Imagine a Combination Lock

Think of a bike lock with 4 digits (0-9). The total combinations are 10,000. A computer can guess this in a fraction of a second.

Now, imagine a lock with 26 letters + 10 digits + 30 symbols. And instead of 4 slots, it has 16 slots. The number of possibilities becomes astronomical.

"Length always beats complexity."

The Math: Why Length Matters

Many people think P@ss! is a strong password because it has symbols. It's not. It's too short.

Mathematically, a 20-character password made of just lowercase letters is actually harder to crack than an 8-character password with symbols. This is because every character you add multiplies the difficulty exponentially.

How High Should Your Entropy Be?

Our Bento Password Generator is designed to maximize entropy. When you select "16 characters" with numbers and symbols, you are creating a key with over 100 bits of entropy.