Resize text area to fit all text on load jquery

Try this

$("textarea").height( $("textarea")[0].scrollHeight );

DEMO

---

UPDATE

As a hack to make it work in older IE-s just add a really short delay before executing it

window.setTimeout( function() {
    $("textarea").height( $("textarea")[0].scrollHeight );
}, 1);​

DEMO

UPDATE FOR MULTIPLE TEXTAREAS

$("textarea").each(function(textarea) {
    $(this).height( $(this)[0].scrollHeight );
});

This worked for me; it loops through all "textarea" elements on page Ready, and set their height.

$(function () {
    $("textarea").each(function () {
        this.style.height = (this.scrollHeight+10)+'px';
    });
});

You can also combine it with an auto-expand function, to make it fully dynamic while writing as well:

function autoresize(textarea) {
    textarea.style.height = '0px';     //Reset height, so that it not only grows but also shrinks
    textarea.style.height = (textarea.scrollHeight+10) + 'px';    //Set new height
}

and call that from an "keyup" event or through jQuery:

$('.autosize').keyup(function () {
    autoresize(this);
});

Note how I am adding 10px to the scroll height: here you can adjust the amount of space you would like the bottom of the text area to give the user.

Hope that helps someone. :)

Edit: Changed answer according to @Mariannes comment.