Forcing Web-Site to Show in Landscape Mode Only

How do you force a website to be in landscape mode when viewed on a mobile device?

Short answer, you can't and you shouldn't control a user's OS behaviour via a website.

You can display a warning using the answer on the following question:
forcing web-site to show in landscape mode only

Or you can force your layout to look like landscape even in portrait mode using the following code (taken from http://www.quora.com/Can-I-use-Javascript-to-force-a-mobile-browser-to-stay-in-portrait-or-landscape-mode):

@media screen and (orientation:landscape) {

  #container {
    -ms-transform: rotate(-90deg); /* IE 9 */
    -webkit-transform: rotate(-90deg); /* Chrome, Safari, Opera */
    transform: rotate(-90deg);
    width: /* screen width */ ;
    height: /* screen height */ ;
    overflow: scroll;
  }
}

As the second site recommends though, you should try and make your site look good however the user wishes to view it.

Force “landscape” orientation mode

It is now possible with the HTML5 webapp manifest. See below.

Original answer:

You can't lock a website or a web application in a specific orientation. It goes against the natural behaviour of the device.

You can detect the device orientation with CSS3 media queries like this:

@media screen and (orientation:portrait) {
    // CSS applied when the device is in portrait mode
}

@media screen and (orientation:landscape) {
    // CSS applied when the device is in landscape mode
}

Or by binding a JavaScript orientation change event like this:

document.addEventListener("orientationchange", function(event){
    switch(window.orientation) 
    {  
        case -90: case 90:
            /* Device is in landscape mode */
            break; 
        default:
            /* Device is in portrait mode */
    }
});

Update on November 12, 2014: It is now possible with the HTML5 webapp manifest.

As explained on html5rocks.com, you can now force the orientation mode using a manifest.json file.

You need to include those line into the json file:

{
    "display":      "standalone", /* Could be "fullscreen", "standalone", "minimal-ui", or "browser" */
    "orientation":  "landscape", /* Could be "landscape" or "portrait" */
    ...
}

And you need to include the manifest into your html file like this:

<link rel="manifest" href="manifest.json">

Not exactly sure what the support is on the webapp manifest for locking orientation mode, but Chrome is definitely there. Will update when I have the info.

Related Topics