How long should a good password be in 2026?

Security experts and the NIST guidelines recommend at least 12 to 16 characters for standard consumer accounts, and 20+ characters for critical credentials such as your password manager master password, primary email, or financial accounts. Every added character exponentially increases the computational work required to crack the password.

Is a 4-word passphrase stronger than a 12-character random password?

Often yes! A 4-word passphrase chosen randomly from a large dictionary (e.g. 'correct-horse-battery-staple') provides approximately 50–60 bits of entropy while being significantly easier for humans to remember and type without error. A 16-character random password with symbols yields ~105 bits of entropy, which is ideal for password managers.

Why does this generator use crypto.getRandomValues instead of Math.random?

Standard JavaScript Math.random() is a pseudo-random number generator (PRNG) that is deterministic and mathematically predictable if an attacker observes previous outputs. The Web Cryptography API's crypto.getRandomValues() is a Cryptographically Secure Pseudo-Random Number Generator (CSPRNG) backed by your operating system's hardware entropy pool, guaranteeing true unpredictability.

Can I type my existing password to check its strength?

Yes. The password display box is fully editable. You can paste or type any password to analyze its entropy, strength level, and crack time. Toggle the eye icon to mask or reveal characters for privacy on shared displays.

Password Generator & Strength Tester

Q: Does Elixuvo store, log, or transmit my generated passwords?

No, never. All generation, entropy calculation, and strength testing occur 100% inside your browser sandbox using the native Web Cryptography API (crypto.getRandomValues). Not a single character, setting, or password string is ever sent to an external server or stored in any database.

Q: What is password entropy and how is it measured?

Password entropy is a mathematical measure of randomness and unpredictability, measured in bits. It depends on the size of the character pool (lowercase, uppercase, numbers, symbols) and the length of the password: Entropy = Length × log2(Pool Size). A score of 60–80 bits is considered strong, while 80+ bits provides maximum defense against modern offline GPU cluster attacks.

Generate cryptographically secure passwords, memorable passphrases, and PIN codes. Test password strength, Shannon entropy, and brute-force crack time client-side.

Live

Password
Passphrase
PIN
Entropy

Password Generator & Strength Tester

Generate cryptographically secure passwords and passphrases client-side using the Web Cryptography API. Test password strength, estimate brute-force crack times, and analyze entropy in real time.

Your Password (Editable for Testing)

16 chars

Strength:Excellent• 105 bits entropy

Crack Time: Centuries (Trillions of years)

Tip:Maximum security! Exceptionally high entropy. Practically uncrackable by modern standards.

Password Length & Character Options

Password Length (16 characters)

Uppercase (A-Z)ABCDEF...

Lowercase (a-z)abcdef...

Numbers (0-9)012345...

Symbols (!@#$)!@#$%^&*...

Avoid ambiguous characters (exclude 0, O, o, 1, l, I, | for easier manual typing)

Bulk Generator

Quickly generate 5, 10, or 20 passwords at once for batch account provisioning or secure exports.

Session History

Last 1 generated

kP9$vL2#mQ8*wR5!

100% In-Browser Cryptographic Generation: Passwords are created using crypto.getRandomValues() from your operating system's cryptographic entropy pool. Zero network requests, zero logging, and zero telemetry.

Why Do You Need a Secure Password Generator?

Over 80% of data breaches involve weak, reused, or compromised passwords. Humans are inherently biased toward predictable patterns: birthdates, pet names, dictionary words with simple substitutions (like replacing "a" with "@" or appending "123!"). Cybercriminals use automated dictionary attacks, rainbow tables, and multi-GPU cracking rigs capable of testing over 100 billion guesses per second.

Credential Stuffing

When one service suffers a data leak, hackers use automated bots to test those leaked credentials across thousands of other sites (banking, email, shopping). Unique passwords isolate every breach.

GPU Brute-Force Attacks

Modern high-performance graphics clusters (e.g. 8x NVIDIA RTX 4090 rigs) can brute-force standard 8-character passwords in minutes. 16+ character passwords push crack times into trillions of years.

Zero Human Predictability

CSPRNG mathematical randomness removes all semantic and phonetic patterns, rendering dictionary and rule-based permutation attacks completely ineffective.

How Does This Password Generator Work?

Unlike basic tools that rely on JavaScript's standard Math.random(), Elixuvo uses the W3C standard Web Cryptography API (window.crypto.getRandomValues):

Hardware-Seeded Entropy PoolThe generator taps into your operating system's cryptographically secure pseudo-random number generator (CSPRNG), which gathers true entropy from hardware interrupts, thermal noise, and CPU timing jitter.

Elimination of Modulo BiasWe employ rejection sampling so that character indices are uniformly distributed across the alphabet, ensuring no single letter or symbol appears more frequently than chance allows.

Fisher-Yates Uniform ShuffleTo satisfy security policies that mandate at least one number, one symbol, and one uppercase letter, guaranteed characters are injected and then shuffled uniformly across the entire string.

100% Client-Side Sandbox ExecutionThe entire generator and strength analyzer lives inside your local browser. Your network tab will verify that zero HTTP calls or websockets are opened when generating credentials.

What Makes a Password Strong? (Entropy & Crack Times)

The true strength of a password is defined by information entropy, expressed in bits:

Entropy (bits) = Length × log₂(Character Pool Size)

Below is how password length and complexity translate to brute-force crack times against a modern cracking rig testing 10 billion guesses per second:

Password Type & Length	Character Pool	Entropy (Bits)	GPU Crack Time	Security Level
6 Digits (PIN)	10	~20 bits	Instantaneous (<1 ms)	Very Weak
8 Chars (Letters only)	52	~45 bits	~3.5 seconds	Weak
12 Chars (Mixed + Sym)	94	~78 bits	~950 years	Good
16 Chars (Mixed + Sym)	94	~105 bits	Trillions of years	Strong
24 Chars (Mixed + Sym)	94	~157 bits	Heat death of Universe	Excellent

Frequently Asked Questions (FAQ)

No, never. All generation, entropy calculation, and strength testing occur 100% inside your browser sandbox using the native Web Cryptography API (crypto.getRandomValues). Not a single character, setting, or password string is ever sent to an external server or stored in any database.

Password entropy is a mathematical measure of randomness and unpredictability, measured in bits. It depends on the size of the character pool (lowercase, uppercase, numbers, symbols) and the length of the password: Entropy = Length × log2(Pool Size). A score of 60–80 bits is considered strong, while 80+ bits provides maximum defense against modern offline GPU cluster attacks.

Next Steps with this file

Continue directly into another tool without saving and re-uploading

1-Click Transfer • No re-upload required

developer

Featured

UUID v4 & Password Generator

Generate cryptographically secure bulk UUID v4 identifiers and high-entropy random passwords client-side using the Web Cryptography API.

Base64 Encoder & Decoder

Encode and decode text, JSON, and files to and from Base64. Supports UTF-8 Unicode, URL-safe Base64, and image Data URIs with zero network transfer.

JWT Decoder & Token Inspector

Decode and inspect JSON Web Tokens (JWT) client-side. Inspect header algorithms, payload claims, expiration countdowns, and verify HMAC signatures securely in your browser.

JWT · JSON · Text

Open

Password Type & Length

Character Pool

Entropy (Bits)

GPU Crack Time

Security Level

6 Digits (PIN)

~20 bits

Instantaneous (<1 ms)

Very Weak

8 Chars (Letters only)

~45 bits

~3.5 seconds

Weak

12 Chars (Mixed + Sym)

~78 bits

~950 years

Good

16 Chars (Mixed + Sym)

~105 bits

Trillions of years

Strong

24 Chars (Mixed + Sym)

~157 bits

Heat death of Universe

Excellent

File Downloaded Successfully!

Password Generator & Strength Tester

Password Generator & Strength Tester

Password Length & Character Options

Why Do You Need a Secure Password Generator?

Credential Stuffing

GPU Brute-Force Attacks

Zero Human Predictability

How Does This Password Generator Work?

What Makes a Password Strong? (Entropy & Crack Times)

Frequently Asked Questions (FAQ)

Next Steps with this file

Related tools

UUID v4 & Password Generator

Base64 Encoder & Decoder

JWT Decoder & Token Inspector

Password Generator & Strength Tester

Password Length & Character Options

Why Do You Need a Secure Password Generator?

Credential Stuffing

GPU Brute-Force Attacks

Zero Human Predictability

How Does This Password Generator Work?

What Makes a Password Strong? (Entropy & Crack Times)

Frequently Asked Questions (FAQ)

Next Steps with this file