Password Strength Check


Password Strength

Estimated time to parse

100 times/hour
10 times/second
1000 times/second
10 billion times/second

How to use password strength check

You can easily check the strength of your password by entering characters in the password field.
You can look at strength based on letter length, use of uppercase and lowercase letters, numbers, symbols, and more.
In addition, the estimated value of the time until the password is cracked is also displayed.

Strength is displayed in five levels: "Very Weak", "Weak", "Medium", "Strong", and "Very Strong".
Estimated time to parse is displayed as an estimate based on some circumstances.

  • 100 times/hour - Online attacks against services that limit password authentication attempts.
  • 10 times/second - Online attacks against unrate-limited services.
  • 1000 times/second - Offline attack. (low speed)
  • 10 billion times/second(1e10 times/second) - Offline attack. (high speed)

About strong passwords

Increase password length

The more characters, the longer it will take to crack the password.
At least 12 characters, more is more robust.

A mix of uppercase and lowercase letters, numbers, and symbols

As the number of types of characters used increases, the number of combinations of patterns increases rapidly.
For example, if there are only 26 letters of the alphabet, there are about 300 million ways with 6 digits.However, in the case of 94 types of uppercase letters, lowercase letters, numbers, and symbols, there are about 690 billion ways.

Don't use meaningful words

Using dates such as first and last names and dates of birth makes it easier to guess.
Using a place name or a word found in a dictionary can also make your password easier to crack.

Do not use simple sequences of characters

Sequences such as 12345, 00000, and abcde, as well as numbers and words that are simply rearranged in reverse order, are easier to guess.


Password strength check method

Password strength check is done with "zxcvbn".

In zxcvbn, in addition to checking the strength by the number of characters and the type of characters, we also check whether the same characters are used repeatedly and whether alphabets are used in order.
In addition, checks are performed considering whether frequently used names and characters are used, reversing words, replacing characters, etc.

Passwords entered here are processed locally in your browser without being transferred to a server and are never collected or stored.
The judgment result of this check does not guarantee the security of the password.Please use it as a guideline for safety.