jQuery password strength checker

Question

I\'m quite new to jQuery, and I\'ve written a simple function to check the strength of a password for each keypress.

The idea is that every time a user enters a char

Answer 1

In case you don't want to use jQuery you can use something like this:

function strengthResult(p) {
if(p.length<6 || p.length>18) {
return 'Passwords must be 6-18 characters';
}
var strength = checkStrength(p);
switch(true) {
    case strength<=30:
        return 'Password "'+p+'" ('+strength+') is Very Weak';
        break;
    case strength>30 && strength<=35:
        return 'Password "'+p+'" ('+strength+') is Weak';
        break;
    case strength>35 && strength<=50:
        return 'Password "'+p+'" ('+strength+') is below Average';
        break;        
    case strength>50 && strength<=60:
        return 'Password "'+p+'" ('+strength+') is almost Good';
        break;
    case strength>60 && strength<=70:
        return 'Password "'+p+'" ('+strength+') is Good';
        break;
    case strength>70 && strength<=80:
        return 'Password "'+p+'" ('+strength+') is Very Good';
        break;
    case strength>80 && strength<=90:
        return 'Password "'+p+'" ('+strength+') is Strong';
        break;
    case strength>90 && strength<=100:
        return 'Password "'+p+'" ('+strength+') is Very Strong';
        break;
        default:
				return 'Error';
}
}
function strengthMap(w,arr) {
var c = 0;
var sum = 0;
newArray = arr.map(function(i) {
i = c;
//sum += w-2*i;
sum += w;
c++;
return sum;
});
return newArray[c-1];
}
function checkStrength(p){
var weight;
var extra;
switch(true) {
    case p.length<6:
        return false;
        break;
    case p.length>18:
        return false;
        break;
    case p.length>=6 && p.length<=10:
    		weight = 7;
        extra = 4;
        break;
    case p.length>10 && p.length<=14:
    		weight = 6;
        extra = 3;
        break;
    case p.length>14 && p.length<=18:
    		weight = 5;
        extra = 2.5;
        break;
}
allDigits = p.replace( /\D+/g, '');
allLower = p.replace( /[^a-z]/g, '' );
allUpper = p.replace( /[^A-Z]/g, '' );
allSpecial = p.replace( /[^\W]/g, '' );
if(allDigits && typeof allDigits!=='undefined') {
dgtArray = Array.from(new Set(allDigits.split('')));
dgtStrength = strengthMap(weight,dgtArray);
} else {
dgtStrength = 0;
}
if(allLower && typeof allLower!=='undefined') {
lowArray = Array.from(new Set(allLower.split('')));
lowStrength = strengthMap(weight,lowArray);
} else {
lowStrength = 0;
}
if(allUpper && typeof allUpper!=='undefined') {
upArray = Array.from(new Set(allUpper.split('')));
upStrength = strengthMap(weight,upArray);
} else {
upStrength = 0;
}
if(allSpecial && typeof allSpecial!=='undefined') {
splArray = Array.from(new Set(allSpecial.split('')));
splStrength = strengthMap(weight,splArray);
} else {
splStrength = 0;
}
strength = dgtStrength+lowStrength+upStrength+splStrength;
if(dgtArray.length>0){
strength = strength + extra;
}
if(splStrength.length>0){
strength = strength + extra;
}
if(p.length>=6){
strength = strength + extra;
}
if(lowArray.length>0 && upArray.length>0){
strength = strength + extra;
}
return strength;
}
console.log(strengthResult('5@aKw1'));
console.log(strengthResult('5@aKw13'));
console.log(strengthResult('5@aKw13e'));
console.log(strengthResult('5@aKw13eE'));
console.log(strengthResult('5@aKw13eE!'));
console.log(strengthResult('5@aKw13eE!,'));
console.log(strengthResult('5@aKw13eE!,4'));
console.log(strengthResult('5@aKw13eE!,4D'));
console.log(strengthResult('5@aKw13eE!,4Dq'));
console.log(strengthResult('5@aKw13eE!,4DqJ'));
console.log(strengthResult('5@aKw13eE!,4DqJi'));
console.log(strengthResult('5@aKw13eE!,4DqJi#'));
console.log(strengthResult('5@aKw13eE!,4DqJi#7'));
console.log(strengthResult('5@aKw13eE!,4DqJJ#7'));
console.log(strengthResult('5@aKw33eE!,4DqJJ#7'));

console.log(strengthResult('111111'));
console.log(strengthResult('1111111'));
console.log(strengthResult('11111111'));
console.log(strengthResult('111111111'));
console.log(strengthResult('1111111111'));
console.log(strengthResult('11111111111'));
console.log(strengthResult('111111111111'));
console.log(strengthResult('1111111111111'));
console.log(strengthResult('11111111111111'));
console.log(strengthResult('111111111111111'));
console.log(strengthResult('1111111111111111'));
console.log(strengthResult('11111111111111111'));
console.log(strengthResult('111111111111111111'));

console.log(strengthResult('5@aKw33eE!,4DqJJ#71'));
console.log(strengthResult('11111'));

the above snippet will calculate password strength for passwords from 6 to 18 characters in length. The default value for each unique character is

• 7 points if password 6-10 characters
• 6 points if password 10-14 characters
• 5 points if password 14-18 characters

If a character is repeated in password then it looses 2 points for every repetition.

Extra points are given when the following specifications are met:

• password has at least 6 digits (adds 2.5 or 3 or 4 points)
• password has at least 1 number (adds 2.5 or 3 or 4 points)
• password has at least 1 special character (adds 2.5 or 3 or 4 points)
• password has at least 1 upper-case and 1 lower-case character (adds 2.5 or 3 or 4 points)