Convert letters to lowercase from an array in JS : <p>I have the following code:</p>

<pre><code>var str = "abcabcABCABC"
var chars = str.split("");
var lettersCount = {};
for (var i = 0; i &lt; chars.length;i++)
{
    if (lettersCount[chars[i]] == undefined )
        lettersCount[chars[i]] = 0;
    lettersCount[chars[i]] ++;
}
for (var i in lettersCount)
{
    console.log(i + ' = ' + lettersCount[i]);
}
</code></pre>

<p>This code is counting how many same letters are in a word. What am I trying is to convert the uppercase letters to lowercase so it should show like this: a - 4, b -4, now it shows: a - 2, A - 2.
I've just started with Js so please be good with me. :)</p>
