Question: I think `trim()` doesn't store the trimmed value. 

I apply trim to the result before the user submits their string and it works, it displays properly by removing the extra space. But if I retrieve the trimmed value back, it gives me the original of user's input, it doesn't remove space.

Before I retrieve the user input from the input field, I added `trim()`:

```
input = $("<input type='text'>").val(txt);
input.trim()

```

It doesn't work.

Answer: 
You should assign it back otherwise it's meaningless.

```
txt = txt.trim();
input = $("<input type='text'").val(txt);

```

Note: the above is using the native JavaScript `trim()` method, assuming `txt` is plain string. If your site should support IE8 and below, refer to [this answer](https://stackoverflow.com/a/498995/447356) to see how to add such support.

Update, based on OP comments. Turns out the request is to truncate all inner spaces, same way HTML is doing. To achieve this, plus better support for the trim change this line:

```
var text = $(this).text();

```

To those three:

```
var text = $.trim($(this).text());
while (text.indexOf("  ") > 0)
    text = text.replace("  ", " ");

```

[Updated fiddle](http://jsfiddle.net/bq3tN/6/).
The trim method does not change the original string. You need to attribute its result to a variable to get the result.

```
------------------------------------------

```

Please notice the description at:

<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/Trim>

Description

The trim method returns the string stripped of whitespace from both ends. trim does not affect the value of the string itself.

```
------------------------------------------

```

Besides that, please let me suggest you to refer to the input field by its ID
(eg: $("#texto"))

```
<!doctype html>
<html lang="en">
<head>
  <meta charset="iso-8859-1">
  <title>jQuery.trim demo</title>
  <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
  <script>
   $(document).ready(function(){
     var txt = "         lots of spaces before and after         ";
     alert('pause');
     $("#texto").val("'" + txt.trim() + "'"); // ok
    // $("<input type='text'>").val("'" + txt.trim() + "'"); // nok
   });
 </script>
</head>
<body>
  <input type='text' id="texto" size='40' />
</body>
</html>

```

(example adapted from the page <http://api.jquery.com/jQuery.trim/>)