Strong Password Creation Guide for 2026

About 6 min read

Password strength is critically important for safely using online services. However, many people prioritize memorability and end up setting easily guessable passwords. According to NordPass's 2024 survey, the most commonly used password worldwide is still "123456", which can be cracked in less than one second - for more shocking examples, see our hall of shame of the worst passwords. This article explains specific methods for creating passwords that are difficult for attackers to break, along with practical approaches using passtsuku.com.

Why You Need a Strong Password

The most common password cracking methods are brute-force attacks and dictionary attacks. Brute-force attacks try every possible character combination in sequence. Dictionary attacks attempt to break in using lists of commonly used passwords like "password", "123456", and "qwerty".

The reason these attacks are effective comes down to computational complexity. The number of password combinations is determined by "the number of available characters raised to the power of the password length." With only 26 lowercase letters and 6 characters, that's 26^6 = approximately 300 million combinations. However, modern GPUs can perform billions of hash calculations per second, meaning all patterns can be tried in less than one second. This is the fundamental reason why short passwords are dangerous.

According to a survey by IPA (Information-technology Promotion Agency, Japan), a 6-character lowercase-only password can be cracked in just seconds. A 2025 study by Hive Systems reported that using the latest GPU (NVIDIA RTX 5090), an 8-character lowercase-only password can be brute-forced in just minutes. Processing performance has significantly improved compared to the previous generation RTX 4090, and the danger of short passwords increases every year. On the other hand, a password of 16 or more characters combining uppercase, lowercase, numbers, and symbols would take trillions of years to crack even with the latest GPUs. Password length and character diversity hold the key to security.

For those who want to systematically learn the basics of password strength,security fundamentals books on Amazon are also a helpful reference.

Three Requirements for a Strong Password

Requirement 1: Ensure Sufficient Length

The factor that most significantly affects password strength is "length." NIST's SP 800-63B guidelines set the minimum password length at 8 characters, but the current consensus among security experts is a minimum of 12 characters, with 16 or more recommended. Each additional character multiplies the number of combinations by the character set size - for example, with 95 character types, adding just one character increases candidates by 95 times. On passtsuku.com, you can freely set the length from 4 to 128 characters simply by adjusting the slider. Start by setting it to 16 characters or more.

Requirement 2: Combine Multiple Character Types

Including all four types - uppercase letters (A–Z), lowercase letters (a–z), numbers (0–9), and symbols (!@#$%, etc.) - dramatically improves password strength. On passtsuku.com, you can select character types using toggle switches at the top of the screen. Unless there is a specific reason not to, we recommend enabling all four types.

For example, an 8-character password using only lowercase letters has about 209 billion combinations (26^8), but an 8-character password using all four types (approximately 95 characters) increases to about 6.3 quadrillion combinations (95^8). Simply increasing character types raises the cracking difficulty by orders of magnitude. To understand this strength difference numerically, see ourarticle on password entropy.

Requirement 3: Use Random Character Strings

Passwords created by humans unconsciously develop patterns. Combinations of names and birthdays, strings following keyboard layouts (like "asdfghjk"), and words with numbers appended (like "Summer2024") are likely included in attacker lists and are dangerous.

passtsuku.com generates passwords using cryptographically secure random numbers. Since no human habits or biases are involved, you get truly random character strings. All generation processing is completed within the browser, and passwords are never transmitted externally over the network.

Using the passtsuku.com Strength Meter

passtsuku.com features a strength meter that displays the strength of generated passwords in real time. This strength meter is calculated based on "entropy," a metric from information theory.

Entropy is expressed in bits, and a higher value means the password is harder to guess. Specifically, each additional bit of entropy doubles the number of candidates. This means an 80-bit password has 2^40 (approximately 1 trillion) times more candidates than a 40-bit password. Use the following guidelines as a reference.

• 35 bits or less: Weak - insufficient for online services
• 36–59 bits: Somewhat weak - acceptable for non-critical services
• 60–119 bits: Strong - suitable from general web services to financial services
• 120 bits or more: Very strong - highest level of security

Using all four types - uppercase, lowercase, numbers, and symbols - with 16 characters yields approximately 105 bits of entropy. This is sufficient strength even for financial services. Aim for 80 bits or more for important accounts.

Common Misconception: Is "Adding a Symbol" Really Enough?

The misconception that "adding one symbol to a password makes it secure" persists. For example, a password like "password1!" with just a number and symbol appended is easily broken by rule-based dictionary attacks. Attackers are well aware of the "common word + number + symbol" pattern and incorporate such transformation rules into their dictionaries.

What truly matters is not adding character types per se, but the overall randomness of the password. "P@ssw0rd!" contains all four character types, but since the original word "Password" is easily guessable, its actual strength is not as high as it appears. Using a random generation tool like passtsuku.com to create strings completely free from human prediction patterns leads to true security.

Password Patterns to Avoid

No matter how long a password is, the following patterns are easily detected by attackers and should be avoided.

The patterns humans tend to use in passwords have historical roots - see our article on the history and culture of passwords for a deeper look at why we keep making the same mistakes.

• Using dictionary words as-is ("password", "dragon", "monkey")
• Strings based on personal information (name, birthday, phone number, pet's name)
• Strings following keyboard layout ("qwerty", "1234567890")
• Repeated characters ("aaaaaa", "111111")
• Reusing previously leaked passwords
• Using the same password across multiple services

Using random passwords generated by passtsuku.com eliminates the risk of falling into these patterns. Generate a different password for each service and manage them with apassword manager for the safest approach.

As a note, the master password for the password manager itself needs to be particularly strong. If the master password is compromised, all stored passwords are at risk. We recommend a random string of 20 or more characters for the master password.

For more details on why password reuse is dangerous and its specific mechanisms,cybersecurity books on Amazon also provide thorough explanations.

Password Strength Self-Check List

Check whether your current passwords are sufficiently secure using the checklist below. If even one answer is "no," we recommend generating a new password with passtsuku.com.

• Is it at least 12 characters long?
• Does it include at least 3 of the 4 types: uppercase, lowercase, numbers, and symbols?
• Does it avoid containing dictionary words as-is?
• Does it avoid personal information like names, birthdays, or phone numbers?
• Is it not reused across other services?
• Has it not been exposed in past data breaches? (Verifiable via Have I Been Pwned, etc.)
• Is it managed with a password manager?

Comparing Password Management Methods

After generating secure passwords, how you manage them is crucial. Let's compare the pros and cons of the main management methods.

• Dedicated password manager: Centralized management in an encrypted vault with auto-fill support. Managing the master password is the most critical concern
• Browser built-in save feature: Convenient, but sync and security levels vary by product. See Browser Password Save Feature Safety for details
• Paper notes: Resistant to remote attacks since they're offline, but there's a risk of physical loss or theft. Must be stored in a secure location like a safe
• Spreadsheets or text files: Not recommended as they're unencrypted. If the PC is infected with malware, all passwords could be exposed at once

Comparing Password Generation Methods

There are several options for generating passwords. Understand the characteristics of each and choose the method that suits you best.

Manually created passwords inevitably reflect human thinking patterns, making them easier for attackers to guess. Browser auto-generation is convenient but may have limited customization for length and character types. passtsuku.com uses cryptographically secure random numbers, allows free configuration of length and character types, and lets you instantly verify entropy with the strength meter. The ability to use it directly from the browser without installation is also a major advantage.

Recommended Settings on passtsuku.com

Finally, here is a summary of recommended settings for generating secure passwords with passtsuku.com.

• Length: 16 characters or more (20+ for important accounts)
• Uppercase letters: On
• Lowercase letters: On
• Numbers: On
• Symbols: On (if the service allows them)

Some services restrict the use of symbols. In that case, turn off symbols and increase the length to 20 or more characters to ensure sufficient strength. If the passtsuku.com strength meter shows 80 bits or more of entropy, you can use the password with confidence.

What Should You Actually Do - Advice by Level

After reading this far, you might feel overwhelmed with information and unsure where to start. Here's a breakdown of what to do right now, organized by level.

For Beginners: Start with Just These 3 Steps

If you're new to password security, just practicing these 3 steps will significantly improve your safety.

1. Generate a password of 16 or more characters on passtsuku.com and set it for your main email account. Email accounts are used for password resets on other services, so they should be protected first
2. Save the generated password in your browser's save feature. It's safer and more convenient than writing it in a notebook
3. Set up two-factor authentication for your email and bank accounts. Even if your password is leaked, two-factor authentication can prevent unauthorized login

For Intermediate Users: Toward Serious Password Management

If you already have basic measures in place, aim for more advanced password management.

1. Use a different password for every service. Password reuse means one service's breach directly leads to compromise of all accounts
2. Adopt a password manager and generate a master password of 20 or more random characters using passtsuku.com
3. Regularly check your email address for breaches on Have I Been Pwned, and immediately change passwords for any compromised services
4. Set passwords with 100 bits or more of entropy for important accounts (financial, email, cloud storage)

What You Can Do Right Now

1. Generate a password of 16 or more characters on passtsuku.com and set it for your main email account
2. Enable two-factor authentication for your email and bank accounts
3. Check your email address for breaches on Have I Been Pwned (haveibeenpwned.com)
4. List your reused passwords and gradually change them to unique passwords for each service
5. Consider adopting a password manager and generate the master password with passtsuku.com

Frequently Asked Questions

How long should a secure password be?

At least 12 characters, with 16 or more recommended. While NIST guidelines set 8 characters as the minimum, security experts now commonly recommend 16 or more.

Is adding symbols to a password enough to make it secure?

Adding symbols alone is not enough. Passwords like "password1!" with symbols appended are easily cracked by dictionary attacks. What matters is the overall randomness of the password.

I can't remember passwords created by a generator. What should I do?

We recommend using a password manager. You only need to remember one master password, and all other passwords are auto-filled. Set a random string of 20 or more characters for your master password.