# .fadeToggle()

Categories: Effects | Effects > Fading

## .fadeToggle( [duration] [, easing] [, callback] ) Returns: jQuery

Description: Display or hide the matched elements by animating their opacity.

- #### version added: 1.4.4.fadeToggle( [duration] [, easing] [, callback] )

  durationA string or number determining how long the animation will run.

  easingA string indicating which easing function to use for the transition.

  callbackA function to call once the animation is complete.

The `.fadeToggle()` method animates the opacity of the matched elements. When called on a visible element, the element's `display` style property is set to `none` once the opacity reaches 0, so the element no longer affects the layout of the page.

Durations are given in milliseconds; higher values indicate slower animations, not faster ones. The strings `'fast'` and `'slow'` can be supplied to indicate durations of `200` and `600` milliseconds, respectively.

#### Easing

The string representing an easing function specifies the speed at which the animation progresses at different points within the animation. The only easing implementations in the jQuery library are the default, called `swing`, and one that progresses at a constant pace, called `linear`. More easing functions are available with the use of plug-ins, most notably the jQuery UI suite.

#### Callback Function

If supplied, the callback is fired once the animation is complete. This can be useful for stringing different animations together in sequence. The callback is not sent any arguments, but `this` is set to the DOM element being animated. If multiple elements are animated, it is important to note that the callback is executed once per matched element, not once for the animation as a whole.

As of jQuery 1.6, the `.promise()` method can be used in conjunction with the `deferred.done()` method to execute a single callback for the animation as a whole when all matching elements have completed their animations ( See the example for .promise() ).

### Additional Notes:

- All jQuery effects, including `.fadeToggle()`, can be turned off globally by setting `jQuery.fx.off = true`, which effectively sets the duration to 0. For more information, see jQuery.fx.off.
- Because of the nature of `requestAnimationFrame()`, you should never queue animations using a `setInterval` or `setTimeout` loop. In order to preserve CPU resources, browsers that support `requestAnimationFrame` will not update animations when the window/tab is not displayed. If you continue to queue animations via `setInterval` or `setTimeout` while animation is paused, all of the queued animations will begin playing when the window/tab regains focus. To avoid this potential problem, use the callback of your last animation in the loop, or append a function to the elements `.queue()` to set the timeout to start the next animation.

### Example:

#### Fades first paragraph in or out, completing the animation within 600 milliseconds and using a linear easing. Fades last paragraph in or out for 200 milliseconds, inserting a "finished" message upon completion.

    <!DOCTYPE html>
    <html>
    <head>
      <script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
    </head>
    <body>

    <button>fadeToggle p1</button>
    <button>fadeToggle p2</button>
    <p>This paragraph has a slow, linear fade.</p>

    <p>This paragraph has a fast animation.</p>
    <div id="log"></div>

    <script>
    $("button:first").click(function() {
      $("p:first").fadeToggle("slow", "linear");
    });
    $("button:last").click(function () {
      $("p:last").fadeToggle("fast", function () {
        $("#log").append("<div>finished</div>");
      });
    });
    </script>

    </body>
    </html>

#### Demo: