CSS Center an iFrame Horizontally and Vertically

So this is a quick article to demo how to center an iframe horizontally and vertically in a screen/viewport in pure CSS (no JavaScript allowed). This CSS centers it by its center point rather than the top/bottom/left/right outline.

On a mobile, a client's site uses an external page embedded by iframe. When the app within the iframe has an alert message, it popups a div at the centre of its app. The alert message is always at the center of the iframe but if the iframe has a height of 2000 pixels, the iframe gets aligned to the top of the parent...

We're going to use a touch of CSS and instead of determining heights and alignment with JS. The following code will work with DIV layers but in this case, also works on iframes:

        <title>Horizontally and Vertically Centered Iframe</title>
        <iframe src="https://www.joellipman.com/examples/html/modal.html" width="350" height="2000"></iframe>

body { 
iframe {
    position: fixed;
    top: 50%;
    transform: translate(-50%, -50%); 

See my JSFiddle demo: https://jsfiddle.net/Jlipman/u5sew3ob/21
and modify the height of the iframe then click on 'Run'. The iframe is always centered even if the top is off screen.
Centered Modal where Iframe height is 200 pixels
Centered Modal where Iframe height is 450 pixels

Related Articles

Joes Revolver Map


Badge - Certified Zoho Creator Associate
Badge - Certified Zoho Creator Associate

Donate & Support

If you like my content, and would like to support this sharing site, feel free to donate using a method below:

Donate to Joel Lipman via PayPal

Donate to Joel Lipman with Bitcoin - Valid till 8 May 2022 3QnhmaBX7LQSRsC9hh6Je9rGQKEGNQNfPb
© 2021 Joel Lipman .com. All Rights Reserved.