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JavaScript RegEx, check if string contains * symbol and follows a set of specific rules [duplicate]

I want a regular expression to check that:
A password contains at least eight characters, including at least one number and includes both lower and uppercase letters and special characters, for example #, ?, !.
It cannot be your old password or contain your username, "password", or "websitename"
And here is my validation expression which is for eight characters including one uppercase letter, one lowercase letter, and one number or special character.
(?=^.{8,}$)((?=.*\d)|(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$"
How can I write it for a password must be eight characters including one uppercase letter, one special character and alphanumeric characters?

Minimum eight characters, at least one letter and one number:
"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$"
Minimum eight characters, at least one letter, one number and one special character:
"^(?=.*[A-Za-z])(?=.*\d)(?=.*[#$!%*#?&])[A-Za-z\d#$!%*#?&]{8,}$"
Minimum eight characters, at least one uppercase letter, one lowercase letter and one number:
"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d]{8,}$"
Minimum eight characters, at least one uppercase letter, one lowercase letter, one number and one special character:
"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$!%*?&])[A-Za-z\d#$!%*?&]{8,}$"
Minimum eight and maximum 10 characters, at least one uppercase letter, one lowercase letter, one number and one special character:
"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$!%*?&])[A-Za-z\d#$!%*?&]{8,10}$"

You may use this regex with multiple lookahead assertions (conditions):
^(?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9])(?=.*?[#?!#$%^&*-]).{8,}$
This regex will enforce these rules:
At least one upper case English letter, (?=.*?[A-Z])
At least one lower case English letter, (?=.*?[a-z])
At least one digit, (?=.*?[0-9])
At least one special character, (?=.*?[#?!#$%^&*-])
Minimum eight in length .{8,} (with the anchors)

Regular expressions don't have an AND operator, so it's pretty hard to write a regex that matches valid passwords, when validity is defined by something AND something else AND something else...
But, regular expressions do have an OR operator, so just apply DeMorgan's theorem, and write a regex that matches invalid passwords:
Anything with less than eight characters OR anything with no numbers OR anything with no uppercase OR or anything with no lowercase OR anything with no special characters.
So:
^(.{0,7}|[^0-9]*|[^A-Z]*|[^a-z]*|[a-zA-Z0-9]*)$
If anything matches that, then it's an invalid password.

Use the following Regex to satisfy the below conditions:
Conditions:
Min 1 uppercase letter.
Min 1 lowercase letter.
Min 1 special character.
Min 1 number.
Min 8 characters.
Max 30 characters.
Regex:
/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$#!%&*?])[A-Za-z\d#$#!%&*?]{8,30}$/

Just a small improvement for #anubhava's answer: Since special character are limited to the ones in the keyboard, use this for any special character:
^(?=.*?[A-Z])(?=(.*[a-z]){1,})(?=(.*[\d]){1,})(?=(.*[\W]){1,})(?!.*\s).{8,}$
This regex will enforce these rules:
At least one upper case English letter
At least one lower case English letter
At least one digit
At least one special character
Minimum eight in length

I had some difficulty following the most popular answer for my circumstances. For example, my validation was failing with characters such as ; or [. I was not interested in white-listing my special characters, so I instead leveraged [^\w\s] as a test - simply put - match non word characters (including numeric) and non white space characters. To summarize, here is what worked for me...
at least 8 characters
at least 1 numeric character
at least 1 lowercase letter
at least 1 uppercase letter
at least 1 special character
/^(?=.*?[A-Z])(?=.*?[a-z])(?=.*?[0-9])(?=.*?[^\w\s]).{8,}$/
JSFiddle Link - simple demo covering various cases

 
✅ The following 4 regex patterns can help you to write almost any password validation
 
 
Pattern 1:
 
Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one special character, no space, and it must be 8-16 characters long.
/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*\W)(?!.* ).{8,16}$/
 
Explanation:
 
(?=.*[0-9]) means that the password must contain a single digit from 1 to 9.
 
(?=.*[a-z]) means that the password must contain one lowercase letter.
 
(?=.*[A-Z]) means that the password must contain one uppercase letter.
 
(?=.*\W) means that the password must contain one special character.
 
.{8,16} means that the password must be 8-16 characters long. We must use this at the end of the regex, just before the $ symbol.
 
What are ^ and $:
 
^ indicates the beginning of the string. $ indicates the end of the string.
If we don't use these ^ & $, the regex will not be able to determine the maximum length of the password. In the above example, we have a condition that the password can't be longer than 16 characters, to make that condition work, we have used these ^ & $
 
Remove maximum length restriction:
 
Instead of .{8,16}, if we used .{8,}, it would mean that the password must be at least 8 characters long. So, there will not be any condition for checking the maximum length of the password.
 
Don't accept any number(digit):
 
Instead of (?=.*[0-9]), if we used (?!.*[0-9]), it would mean that the password must not contain any digit from 1-9 (Difference with the (?=.*[0-9]) is the use of ! instead of =)
 
Don't accept any spcecial character:
 
Instead of (?=.*\W), if we used (?!.*\W), it would mean that the password must not contain any special characters (The difference with the (?=.*\W) is the use of ! instead of =)
 
Alternative Syntax for number(digit):
 
Instead of (?=.*[0-9]), we could have used (?=.*\d). (?=.*\d) also means that the password must contain a single digit from 1 to 9.
 
 
Pattern 2:
 
Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one underscore but no other special character, no space and it must be 8-16 characters long.
/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*_)(?!.*\W)(?!.* ).{8,16}$/
 
Difference with the Pattern 1
 
Here, we have used (?=.*_) which wasn't on the Pattern 1.
 
(?=.*_)(?!.*\W) means that the password must contain an underscore but can not contain any other special character.
 
Pattern 3:
 
Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, one underscore, no space and it must be 8-16 characters long. Usage of any other special character other than underscore is optional.
/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*_)(?!.* ).{8,16}$/
 
Difference with the Pattern 2
 
Here, we have not used (?!.*\W) what was on the Pattern 2.
 
But it still has the (?=.*_)
 
By just removing the (?!.*\W), special characters have become optional. Now, one underscore is required but any other special character can be used or not as it's optional.
 
Pattern 4:
 
Password must contain one digit from 1 to 9, one lowercase letter, one uppercase letter, and one underscore, and it must be 8-16 characters long. Usage of any other special character and usage of space is optional.
/^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z]).{8,16}$/
 
Difference with the Pattern 3
 
Here, we have not used (?=.*_) & (?!.* ) which was on the Pattern 3.
 
By removing (?=.*_), it's no longer mandatory to pass one underscore. Now, passing special characters is optional.
 
By removing the (?!.* ), usage of space has become optional too.

I would reply to Peter Mortensen, but I don't have enough reputation.
His expressions are perfect for each of the specified minimum requirements. The problem with his expressions that don't require special characters is that they also don't ALLOW special characters, so they also enforce maximum requirements, which I don't believe the OP requested. Normally you want to allow your users to make their password as strong as they want; why restrict strong passwords?
So, his "minimum eight characters, at least one letter and one number" expression:
^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$
achieves the minimum requirement, but the remaining characters can only be letter and numbers. To allow (but not require) special characters, you should use something like:
^(?=.*[A-Za-z])(?=.*\d).{8,}$ to allow any characters
or
^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d$#$!%*#?&]{8,}$ to allow specific special characters
Likewise, "minimum eight characters, at least one uppercase letter, one lowercase letter and one number:"
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d]{8,}$
meets that minimum requirement, but only allows letters and numbers. Use:
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{8,}$ to allow any characters
or
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[A-Za-z\d$#$!%*?&]{8,} to allow specific special characters.

A more "generic" version(?), allowing none English letters as special characters.
^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$
var pwdList = [
'##V4-\3Z`zTzM{>k',
'12qw!"QW12',
'123qweASD!"#',
'1qA!"#$%&',
'Günther32',
'123456789',
'qweASD123',
'qweqQWEQWEqw',
'12qwAS!'
],
re = /^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$/;
pwdList.forEach(function (pw) {
document.write('<span style="color:'+ (re.test(pw) ? 'green':'red') + '">' + pw + '</span><br/>');
});

Import the JavaScript file jquery.validate.min.js.
You can use this method:
$.validator.addMethod("pwcheck", function (value) {
return /[\#\#\$\%\^\&\*\(\)\_\+\!]/.test(value) && /[a-z]/.test(value) && /[0-9]/.test(value) && /[A-Z]/.test(value)
});
At least one upper case English letter
At least one lower case English letter
At least one digit
At least one special character

For standard password requirements I found this to be useful:
At least 1 alphabet
At least 1 digit
Contains no space
Optional special characters e.g. #$!%*#?&^_-
Minimum 8 characters long
/^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d#$!%*#?&^_-]{8,}$/
You can also set the upper limit for example {8,32} up to 32 characters long.

Try this one:
Minimum six characters
At least one uppercase character
At least one lowercase character
At least one special character
Expression:
"/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$#$!%*?&.])[A-Za-z\d$#$!%*?&.]{6, 20}/"
Optional Special Characters:
At least one special character
At least one number
Special characters are optional
Minimum six characters and maximum 16 characters
Expression:
"/^(?=.*\d)(?=.*[a-zA-Z]).{6,20}$/"
If the min and max condition is not required then remove .{6, 16}
6 is minimum character limit
20 is maximum character limit
?= means match expression

This worked for me:
^(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[#$!%*?&])([a-zA-Z0-9#$!%*?&]{8,})$
At least 8 characters long;
One lowercase, one uppercase, one number and one special character;
No whitespaces.

Not directly answering the question, but does it really have to be a regex?
I used to do lots of Perl, and got used to solving problems with regexes. However, when they get more complicated with all the look-aheads and other quirks, you need to write dozens of unit tests to kill all those little bugs.
Furthermore, a regex is typically a few times slower than an imperative or a functional solution.
For example, the following (not very FP) Scala function solves the original question about three times faster than the regex of the most popular answer. What it does is also so clear that you don't need a unit test at all:
def validatePassword(password: String): Boolean = {
if (password.length < 8)
return false
var lower = false
var upper = false
var numbers = false
var special = false
password.foreach { c =>
if (c.isDigit) numbers = true
else if (c.isLower) lower = true
else if (c.isUpper) upper = true
else special = true
}
lower && upper && numbers && special
}

For a more strict validation where the following is required:
At least One Upper Case Character
At least one Lower Case character
At least one digit
At least one symbol/special character #$!%*#?&^_-
Minimum 8 characters/digits
Regex:
/(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[#$!%*#?&^_-]).{8,}/
I hope it helps someone with a more stringent.

What about considering the following regex solution:
^(?=.*[\w])(?=.*[\W])[\w\W]{8,}$
Which validates the following:
At least one lowercase
At least one uppercase
At least one digit
At least one special character
At least it should have 8 characters long.
Check it out working at the following link https://regex101.com/r/qPmC06/4/

^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9])(?=.*[!##$%^&*()_+,.\\\/;':"-]).{8,}$

Another option is to make use of contrast in the lookahead assertions using a negated character class, optionally matching any character except that is listed before matching the character that should be matched.
^(?=[^A-Z\n]*[A-Z])(?=[^a-z\n]*[a-z])(?=[^0-9\n]*[0-9])(?=[^#?!#$%^&*\n-]*[#?!#$%^&*-]).{8,}$
See a regex demo
In parts, the pattern matches:
^ Start of string
(?=[^A-Z\n]*[A-Z]) Positive lookahead, assert 0+ times any char except A-Z or a newline. Then match a char A-Z
(?=[^a-z\n]*[a-z]) The same approach for a char a-z
(?=[^0-9\n]*[0-9]) The same approach for a digit 0-9
(?=[^#?!#$%^&*\n-]*[#?!#$%^&*-]) The same approach for a char that you would consider special
.{8,} Match 8 or more times any character except a newline
$ End of string
Notes
A dot can also match a space. If you do not want to allow matching a space, then .{8,} can be changed to \S{8,} to match 8 or more non whitespace characters
Using either . or \S can match more characters than are specified in the lookahead assertions. If you only want to match the characters that are used in the assertions, you can change .{8,} to match only the allowed characters [#?!#$%^&*A-Za-z0-9-]{8,} using a character class
const regex = /^(?=[^A-Z\n]*[A-Z])(?=[^a-z\n]*[a-z])(?=[^0-9\n]*[0-9])(?=[^#?!#$%^&*\n-]*[#?!#$%^&*-]).{8,}$/;
[
"abcA1#!A",
"#!asdfSFD1;",
"# a f F1 ;",
"1111111111",
"aaaaaaaa",
"11111111",
"AAAAAAAA",
"########",
"aA1#"
].forEach(s =>
console.log(regex.test(s) ? `Match --> ${s}` : `No match --> ${s}`)
);

/^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9]).*$/
this the simple way to use it while validate atleast 1 uppercase 1 lowercase and 1 number
and this is the example while I use in express validation
check('password')
.notEmpty()
.withMessage('Password cannot be null')
.bail()
.isLength({ min: 6 })
.withMessage('Password must be at least 6 characters')
.bail()
.matches(/^(?=.*[A-Z])(?=.*[a-z])(?=.*[0-9]).*$/)
.withMessage(
'Must have atleast 1 uppercase, 1 lowercase letter and 1 number'
),

Testing this one in 2020:
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$!%*?&])[A-Za-z\d#$!%*?&]{8,}$
Verify yourself
const regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$!%*?&])[A-Za-z\d#$!%*?&]{8,}$/;
const str = `some12*Nuts`;
let m;
if ((m = regex.exec(str)) !== null) {
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}

#ClasG has already suggested:
^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*[^\w\s])\S{8,}$
but it does not accept _(underscore) as a special character (eg. Aa12345_).
An improved one is:
^(?=\S*[a-z])(?=\S*[A-Z])(?=\S*\d)(?=\S*([^\w\s]|[_]))\S{8,}$

I've found many problems here, so I made my own.
Here it is in all it's glory, with tests:
^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*([^a-zA-Z\d\s])).{9,}$
https://regex101.com/r/DCRR65/4/tests
Things to look out for:
doesn't use \w because that includes _, which I'm testing for.
I've had lots of troubles matching symbols, without matching the end of the line.
Doesn't specify symbols specifically, this is also because different locales may have different symbols on their keyboards that they may want to use.

Demo:
function password_check() {
pass = document.getElementById("password").value;
console.log(pass);
regex = /^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[#$!%*?&])[A-Za-z\d#$!%*?&]{8,}$/;
if (regex.exec(pass) == null) {
alert('invalid password!')
}
else {
console.log("valid");
}
}
<input type="text" id="password" value="Sample#1">
<input type="button" id="submit" onclick="password_check()" value="submit">

var strongRegex = new RegExp("^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[!##\$%\^&\*])(?=.{8,})");
var mediumRegex = new RegExp("^(((?=.*[a-z])(?=.*[A-Z]))|((?=.*[a-z])(?=.*[0-9]))|((?=.*[A-Z])(?=.*[0-9])))(?=.{6,})");
Best For javascript

Keep it simple stupid:
This should do the trick for you, always.
Regex: ^(.{0,7}|[^a-z]{1,}|[^A-Z]{1,}|[^\d]{1,}|[^\W]{1,})$|[\s]
If your password matches the regex above, it is invalid.
If there's no match, your password is valid and contains has at least 8 characters, one upper case letter, one lower case letter and one symbol or special character. And it also contains no spaces, tabs or line breaks.
Breakdown of Regex
.{0,7} - matches if password has between 0 to 7 characters.
[^a-z]{1,} - matches if no lower case is found
[^A-Z]{1,} - matches if no upper case is found
[^\d]{1,} - matches if no number (between [0-9]) is found
[\s] - matches if a white space, tab or line break is found.
With this approach there's no limit or restriction in terms of symbols allowed. If you want to limit to few symbols allowable, just change [^\W] with [^YourSymbols].

(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[##$%^&+-]).{6}

According to your need this pattern should work just fine. Try this,
^(?=(.*\d){1})(.*\S)(?=.*[a-zA-Z\S])[0-9a-zA-Z\S]{8,}
Just create a string variable, assign the pattern, and create a boolean method which returns true if the pattern is correct, else false.
Sample:
String pattern = "^(?=(.*\d){1})(.*\S)(?=.*[a-zA-Z\S])[0-9a-zA-Z\S]{8,}";
String password_string = "Type the password here"
private boolean isValidPassword(String password_string) {
return password_string.matches(Constants.passwordPattern);
}

Use the following Regex to satisfy the below conditions:
Conditions: 1] Min 1 special character.
2] Min 1 number.
3] Min 8 characters or More
Regex: ^(?=.*\d)(?=.*[#$#!%&*?])[A-Za-z\d#$#!%&*?]{8,}$
Can Test Online: https://regex101.com

Just we can do this by using HTML5.
Use below code in pattern attribute,
pattern="(?=^.{8,}$)((?=.*\d)(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$"
It will work perfectly.

You can use the below regular expression pattern to check the password whether it matches your expectations or not.
((?=.*\\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[~!##$%^&*()]).{8,20})

javascript Regex to have atmost 5 characters in password

I am trying to implement maximum case in JavaScript for password validation.
I have a scenario where in password user should enter maximum 5 characters (a-z,A-Z) and password length having no restriction
Passsword length no limit
except (a-z,A-Z) ,there is no limtation
charcter(a-z,A-Z) will have atmost 5 in password .Not more than that.Sequence doesnot matter.
I tried /[^A-Z,a-z]*(?:[A-Z,a-z][^A-Z,a-z]*){0,5}/
But it is not working.
Kindly help

Did you even search? It is obviously, that this is a duplicate.
See
Regex javascript for Minimum 8 characters,at least one number and one special character, maximum 32 characters
Password REGEX with min 6 chars, at least one letter and one number and may contain special characters
JavaScript regex for alphanumeric string with length of 3-5 chars

You can just count how many characters you have in the password like so:
if(password.match(/[a-zA-Z]/g).length > 5){ /* reject */ }

You can use the below regex for password validation.
((?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[##$%]).{5,20})
It validates :
Must contain ! digit [0-9]
One lowercase character [a-z]
One uppercase character [A-Z]
One symbol [##$%]
Length of password must be between [5-20].

Break it down and solve it step by step
Alphabet only - define your character set
/[A-Za-z]/
Maximum length of 5 - use a quantifier
/[A-Za-z]{0,5}/
Nothing else is allowed - wrap it with ^ and $
/^[A-Za-z]{0,5}$/

regex password validation angularjs

I am new to angular js. I have created a login screen. I need to validate my password. it should contain one special character from -'$#£!%*#?&' and at least one letter and number. As of now it accepts all special characters without any limitations. I have following code
if (vm.newpassword_details.password.search("^(?=.*?[A-Za-z])(?=.*?[0-9])(?=.*?[$#£!%*#?&]).{8,}$")) {
var msg = "Password should contain one special character from -'$#£!%*#?&' and at least one letter and number";
alert(msg);
}

Note that your current regex imposes 4 types of restriction:
At least one ASCII letter ((?=.*?[A-Za-z])),
At least one digit ((?=.*?[0-9])),
At least one specific char from the set ((?=.*?[$#£!%*#?&]))
The whole string should have at least 8 chars (.{8,})
The . in .{8,} can match any char other than line break chars.
If you plan to restrict the . and only allow users to type the chars from your sets, create a superset from them and use it with RegExp#test:
if (!/^(?=.*?[A-Za-z])(?=.*?[0-9])(?=.*?[$#£!%*#?&])[A-Za-z0-9$#£!%*#?&]{8,}$/.test(vm.newpassword_details.password)) { /* Error ! */ }
See the regex demo

Check password valid using regex in javascript

The password must be eight characters or longer
The password must contain at least 2 lowercase alphabetical character.
The password must contain at least 2 uppercase alphabetical character.
The password must contain at least 2 numeric character.
The password must contain at least 2 special character.
My code
function checkPass(pw) {
var regx = new RegExp("^(?=.*[a-z]{2})(?=.*[A-Z]{2})(?=.*[0-9]{2})(?=.*[!##\$%\^&\*\)\(]{2})(?=.{8,})");
return regx.test(pw);
}
checkPass('PAssword12#$') => true
checkPass('PaSsword12#$') => false
I want to funtion return true when 2 uppercase character is not sequential.
Thanks!

You need to use the $ anchor to check for length (and best is to move that check out from lookaheads) and to allow some non-uppercase letters in between like this:
function checkPass(pw) {
var regx = /^(?=(?:[^a-z]*[a-z]){2})(?=(?:[^A-Z]*[A-Z]){2})(?=(?:\D*\d){2})(?=(?:[^!##$%^&*)(]*[!##$%^&*)(]){2}).{8,}$/;
return regx.test(pw);
}
document.write(checkPass('PAssword12#$') + "<br>");
document.write(checkPass('PaSsword12#$'));
Note that I used the principle of contrast: (?:[^a-z]*[a-z]){2} matches 2 sequences of symbols other than a-z zero or more times followed by 1 lowercase letter. I modified all the lookaheads the same way.

Rather than having [A-Z]{2} which will only match two uppercase characters together, you'll have to put in an optional match for any other characters in between two separate ranges (you'll have to do this for the lowercase, numbers and symbols as well). So you would instead put
[A-Z].*?[A-Z]
You also don't actually need to check whether it's at least 8 characters, because any password meeting the criteria for lowercase/uppercase letters, numbers and symbols has to be 8 characters at minimum anyway.

Need help: RegEx for a password containing numbers and special chars

I need help with a RegEx for a password. The password must contain at least one special char (like "§$&/!) AND a number.
E.g. a password like "EdfA433&" must be valid whereas "aASEas§ö" not as it contains not a number.
I have the following RegEx so far:
^(?=.*[0-9])(?=.*[a-zA-Z]).{3,}$
But this one is obviously checking only for a number. Can anyone help?

You're better off just using multiple more simple regular expressions: any code checking anything like this won't be performance sensitive, and the additional complexity of maintenance given a more complex regexp probably isn't justifiable.
So, what I'd go for:
var valid = foo.match(/[0-9]/) && foo.match(/["§$&/!]/);
I wonder if you really want to define special characters like that: Does é count as a special character? Does ~ count as a special character?

^(?=.*\d)(?=.*\W).{3,}$
checks for at least one digit (\d) and one non-alphanumeric character (\W). \W is the inverse of \w which matches digits, letters and the underscore.
If you want to include the underscore in the list of "special characters", use
^(?=.*\d)(?=.*[\W_]).{3,}$

I would divide function that checks if password is "hard" into some parts and in each part I would check one condition. You can see some complicated regex on Daily WTF with password reset: http://thedailywtf.com/Articles/The-Password-Reset-Facade.aspx