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How do I auto-resize an image to fit a 'div' container?

How do you auto-resize a large image so that it will fit into a smaller width div container whilst maintaining its width:height ratio?

Example: stackoverflow.com - when an image is inserted onto the editor panel and the image is too large to fit onto the page, the image is automatically resized.

Some interesting libraries for doing image resizing to fit the container: * plugins.jquery.com/project/myimgscale * code.google.com/p/jquery-imagefit-plugin
Aside @Kevin's answer... You can also use services like ImageBoss to create your images with the size you want, on-demand. Fitting the image on the container is great but serving images responsively is way batter.
@jolumg Not quite; while there's a lot of overlap in some solutions, there are also many solutions that are not interchangeable, as that one is asking how to scale an image up, whereas this one is asking to scale an image down.

K
Kevin

Do not apply an explicit width or height to the image tag. Instead, give it:

max-width:100%;
max-height:100%;

Also, height: auto; if you want to specify a width only.

Example: http://jsfiddle.net/xwrvxser/1/

img { max-width: 100%; max-height: 100%; } .portrait { height: 80px; width: 30px; } .landscape { height: 30px; width: 80px; } .square { height: 75px; width: 75px; } Portrait Div

Landscape Div
Square Div


This will not scale both the height and width.
height: auto; if you want to specify a width only
Not applying explicit width and height to the image has the side-effect that the page will not reserve space to the image, and the page will flicker or content might jump as the image loads.
T
TylerH

It turns out there's another way to do this: object-fit.

<img style='height: 100%; width: 100%; object-fit: contain'/>

will do the work. Don't forget to include other necessary attributes like src and alt, of course.

Fiddle: http://jsfiddle.net/mbHB4/7364/


This will scale the image to fit the larger dimension completely within the container, so the smaller dimension may not cover it completely. To crop the larger dimension instead, use object-fit: cover
N
Neil

Currently there is no way to do this correctly in a deterministic way, with fixed-size images such as JPEGs or PNG files.

To resize an image proportionally, you have to set either the height or width to "100%", but not both. If you set both to "100%", your image will be stretched.

Choosing whether to do height or width depends on your image and container dimensions:

If your image and container are both "portrait shaped" or both "landscape shaped" (taller than they are wide, or wider than they are tall, respectively), then it doesn't matter which of height or width are "%100". If your image is portrait, and your container is landscape, you must set height="100%" on the image. If your image is landscape, and your container is portrait, you must set width="100%" on the image.

If your image is an SVG, which is a variable-sized vector image format, you can have the expansion to fit the container happen automatically.

You just have to ensure that the SVG file has none of these properties set in the <svg> tag:

height
width
viewbox

Most vector drawing programs out there will set these properties when exporting an SVG file, so you will have to manually edit your file every time you export, or write a script to do it.


b
bad_coder

Here is a solution that will both vertically and horizontally align your img within a div without any stretching even if the image supplied is too small or too big to fit in the div.

The HTML content:

<div id="myDiv">
  <img alt="Client Logo" title="Client Logo" src="Imagelocation" />
</div>

The CSS content:

#myDiv
{
  height: 104px;
  width: 140px;
}
#myDiv img
{
  max-width: 100%;
  max-height: 100%;
  margin: auto;
  display: block;
}

The jQuery part:

var logoHeight = $('#myDiv img').height();
    if (logoHeight < 104) {
        var margintop = (104 - logoHeight) / 2;
        $('#myDiv img').css('margin-top', margintop);
    }

T
TylerH

You have two ways of making the image responsive.

When an image is a background image. #container{ width: 300px; height: 300px; background-image: url(https://images.fonearena.com/blog/wp-content/uploads/2013/11/Lenovo-p780-camera-sample-10.jpg); background-size: cover; background-repeat: no-repeat; background-position: center; }

Run it here But one should use img tag to put images as it is better than background-image in terms of SEO as you can write keyword in the alt of the img tag. So here is you can make the image responsive. When image is in img tag. #container{ max-width: 400px; overflow: hidden; } img{ width: 100%; object-fit: contain; }
your_keyword
Run it here


P
Peter Mortensen

Make it simple!

Give the container a fixed height and then for the img tag inside it, set width and max-height.

<div style="height: 250px">
     <img src="..." alt=" " style="width: 100%;max-height: 100%" />
</div>

The difference is that you set the width to be 100%, not the max-width.


P
Peter Mortensen

You can set the image as the background to a div, and then use the CSS background-size property:

background-size: cover;

It will "Scale the background image to be as large as possible so that the background area is completely covered by the background image. Some parts of the background image may not be in view within the background positioning area" -- W3Schools


P
Peter Mortensen

Check out my solution: http://codepen.io/petethepig/pen/dvFsA

It's written in pure CSS, without any JavaScript code. It can handle images of any size and any orientation.

Given such HTML:

<div class="image">
  <div class="trick"></div>
  <img src="http://placekitten.com/415/200"/>
</div>

the CSS code would be:

.image {
  font-size: 0;
  text-align: center;
  width: 200px;  /* Container's dimensions */
  height: 150px;
}
img {
  display: inline-block;
  vertical-align: middle;
  max-height: 100%;
  max-width: 100%;
}
.trick {
  display: inline-block;
  vertical-align: middle;
  height: 150px;
}

S
Sergio Reis

There are several ways to fit the image to <div>.

img {
    object-fit: cover;
}

The CSS object-fit property is used to specify how an <img> or <video> should be resized to fit its container.

This property tells the content to fill the container in a variety of ways; such as "preserve that aspect ratio" or "stretch up and take up as much space as possible".

fill - This is default. The image is resized to fill the given dimension. If necessary, the image will be stretched or squished to fit

contain - The image keeps its aspect ratio, but is resized to fit within the given dimension

cover - The image keeps its aspect ratio and fills the given dimension. The image will be clipped to fit

none - The image is not resized

scale-down - the image is scaled down to the smallest version of none or contain

You can find out more working samples here.


a
actimel

I have much better solution without need of any JavaScript. It is fully responsive, and I use it a lot. You often need to fit an image of any aspect ratio to a container element with a specified aspect ratio. And having whole this thing fully responsive is a must.

/* For this demo only */ .container { max-width: 300px; margin: 0 auto; } .img-frame { box-shadow: 3px 3px 6px rgba(0, 0, 0, .15); background: #ee0; margin: 20px auto; } /* This is for responsive container with specified aspect ratio */ .aspect-ratio { position: relative; } .aspect-ratio-1-1 { padding-bottom: 100%; } .aspect-ratio-4-3 { padding-bottom: 75%; } .aspect-ratio-16-9 { padding-bottom: 56.25%; } /* This is the key part - position and fit the image to the container */ .fit-img { position: absolute; top: 0; right: 0; bottom: 0; left: 0; margin: auto; max-width: 80%; max-height: 90% } .fit-img-bottom { top: auto; } .fit-img-tight { max-width: 100%; max-height: 100% }

sample
sample
sample
sample

You can set max-width and max height independently; the image will respect the smallest one (depending on the values and aspect ratio of the image). You can also set image to be aligned as you want (for example, for a product picture on an infinite white background you can position it to center bottom easily).


P
Peter Mortensen

This solution doesn't stretch the image and fills the whole container, but it cuts some of the image.

HTML:

 <div><img src="/images/image.png"></div>

CSS:

div {
    width: 100%;
    height: 10em;
    overflow: hidden;

img {
    min-width: 100%;
    min-height: 100%;
}

P
Peter Mortensen

I just published a jQuery plugin that does exactly what you need with a lot of options:

https://github.com/GestiXi/image-scale

Usage:

HTML

<div class="image-container">
    <img class="scale" data-scale="best-fit-down" data-align="center" src="img/example.jpg">
</div>

JavaScript

$(function() {
    $("img.scale").imageScale();
});

P
Peter Mortensen

I see that many people have suggested object-fit which is a good option. But if you want it to work in older browsers as well, there is another way of doing it easily.

It's quite simple. The approach I took was to position the image inside the container with absolute and then place it right at the centre using the combination:

position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);

Once it is in the centre, I give to the image,

// For vertical blocks (i.e., where height is greater than width)
height: 100%;
width: auto;

// For horizontal blocks (i.e., where width is greater than height)
height: auto;
width: 100%;

This makes the image get the effect of object-fit:cover.

Here is a demonstration of the above logic.

https://jsfiddle.net/furqan_694/s3xLe1gp/

This logic works in all browsers.


C
Chong Lip Phang

The following works perfectly for me:

img{
   height: 99999px;
   object-fit:contain;
   max-height: 100%;
   max-width: 100%;    
   display: block;
   margin: auto auto;
}

It also works perfectly for me as well. Not sure how the commands work together in this case @Chong Lip Phang, especially how height: 99999px is used? I removed it to see the effect and the horizontal centering failed, so it appears that there is no redundancy.
@Vass height:99999px basically tries to enlarge the image while preserving the aspect ratio (width: auto) until the vertical or horizontal bound is reached (max-height or max-width). I think you can also use height:200%; or width:999vw.
While using grid (grid template areas), I found that including overflow-y: hidden; in the upper level div of the grid area to be necessary in a situation I am facing
T
TylerH

I fixed this problem using the following code:

<div class="container"><img src="image_url" /></div>
.container {
    height: 75px;
    width: 75px;
}

.container img {
    object-fit: cover;
    object-position: top;
    display: block;
    height: 100%;
    width: 100%;
}

P
Peter Mortensen
<style type="text/css">
    #container{
        text-align: center;
        width: 100%;
        height: 200px; /* Set height */
        margin: 0px;
        padding: 0px;
        background-image: url('../assets/images/img.jpg');
        background-size: content; /* Scaling down large image to a div */
        background-repeat: no-repeat;
        background-position: center;
    }
</style>

<div id="container>
    <!-- Inside container -->
</div>

P
Peter Mortensen

A simple solution is to use Flexbox. Define the container's CSS to:

.container{
    display: flex;
    justify-content: center;
    align-items: center;
    align-content: center;
    overflow: hidden;
    /* Any custom height */
}

Adjust the contained image width to 100% and you should get a nice centered image in the container with the dimensions preserved.


C
Community

As answered here, you can also use vh units instead of max-height: 100% if it doesn't work on your browser (like Chrome):

img {
    max-height: 75vh;
}

P
Peter Mortensen

I centered and scaled proportionally an image inside a hyperlink both horizontally and vertically this way:

#link {
    border: 1px solid blue;
    display: table-cell;
    height: 100px;
    vertical-align: middle;
    width: 100px;
}
#link img {
    border: 1px solid red;
    display: block;
    margin-left: auto;
    margin-right: auto;
    max-height: 60px;
    max-width: 60px;
}

It was tested in Internet Explorer, Firefox, and Safari.

More information about centering is here.


P
Peter Mortensen

Give the height and width you need for your image to the div that contains the tag. Don't forget to give the height/width in the proper style tag.

In the <img> tag, give the max-height and max-width as 100%.

<div style="height:750px; width:700px;">
    <img alt="That Image" style="max-height:100%; max-width:100%;" src="">
</div>

You can add the details in the appropriate classes after you get it right.


P
Peter Mortensen

The code below is adapted from previous answers and is tested by me using an image called storm.jpg.

This is the complete HTML code for a simple page that displays the image. This works perfect and was tested by me with www.resizemybrowser.com. Put the CSS code at the top of your HTML code, underneath your head section. Put the picture code wherever you want the picture.

<html>
    <head>
        <style type="text/css">
            #myDiv
            {
                  height: auto;
                  width: auto;
            }
            #myDiv img
            {
                max-width: 100%;
                max-height: 100%;
                margin: auto;
                display: block;
            }
        </style>
    </head>

    <body>
        <div id="myDiv">
            <img src="images/storm.jpg">
        </div>
    </body>
</html>

P
Peter Mortensen

You have to tell the browser the height of where you are placing it:

.example {
    height: 220px; /* DEFINE HEIGHT */
    background: url('../img/example.png');
    background-size: 100% 100%;
    background-repeat: no-repeat;
}

P
Peter Mortensen

Edit: Previous table-based image positioning had issues in Internet Explorer 11 (max-height doesn't work in display:table elements). I've replaced it with inline based positioning which not only works fine in both Internet Explorer 7 and Internet Explorer 11, but it also requires less code.

Here is my take on the subject. It'll only work if the container has a specified size (max-width and max-height don't seem to get along with containers that don't have concrete size), but I wrote the CSS content in a way that allows it to be reused (add picture-frame class and px125 size class to your existing container).

In CSS:

.picture-frame
{
    vertical-align: top;
    display: inline-block;
    text-align: center;
}

.picture-frame.px125
{
    width: 125px;
    height: 125px;
    line-height: 125px;
}

.picture-frame img
{
    margin-top: -4px; /* Inline images have a slight offset for some reason when positioned using vertical-align */
    max-width: 100%;
    max-height: 100%;
    display: inline-block;
    vertical-align: middle;
    border: 0; /* Remove border on images enclosed in anchors in Internet Explorer */
}

And in HTML:

<a href="#" class="picture-frame px125">
    <img src="http://i.imgur.com/lesa2wS.png"/>
</a>

DEMO

/* Main style */ .picture-frame { vertical-align: top; display: inline-block; text-align: center; } .picture-frame.px32 { width: 32px; height: 32px; line-height: 32px; } .picture-frame.px125 { width: 125px; height: 125px; line-height: 125px; } .picture-frame img { margin-top: -4px; /* Inline images have a slight offset for some reason when positioned using vertical-align */ max-width: 100%; max-height: 100%; display: inline-block; vertical-align: middle; border: 0; /* Remove border on images enclosed in anchors in Internet Explorer */ } /* Extras */ .picture-frame { padding: 5px; } .frame { border:1px solid black; }

32px

125px

Edit: Possible further improvement using JavaScript (upscaling images):

function fixImage(img)
{
    var $this = $(img);
    var parent = $this.closest('.picture-frame');
    if ($this.width() == parent.width() || $this.height() == parent.height())
        return;

    if ($this.width() > $this.height())
        $this.css('width', parent.width() + 'px');
    else
        $this.css('height', parent.height() + 'px');
}

$('.picture-frame img:visible').each(function
{
    if (this.complete)
        fixImage(this);
    else
        this.onload = function(){ fixImage(this) };
});

There is a drawback to using this method. If the image fails to load, alt text will be displayed with parent container line-height. If alt text has more than one line, it will start looking really bad...
P
Peter Mortensen

The accepted answer from Thorn007 doesn't work when the image is too small.

To solve this, I added a scale factor. This way, it makes the image bigger and it fills the div container.

Example:

<div style="width:400px; height:200px;">
  <img src="pix.jpg" style="max-width:100px; height:50px; transform:scale(4); transform-origin:left top;" />
</div>

Notes:

For WebKit you must add -webkit-transform:scale(4); -webkit-transform-origin:left top; in the style. With a scale factor of 4, you have max-width = 400/4 = 100 and max-height = 200/4 = 50 An alternate solution is to set max-width and max-height at 25%. It's even simpler.


P
Peter Mortensen

A simple solution (4-step fix!!) that seems to work for me, is below. The example uses the width to determine the overall size, but you can also flip it to use the height instead.

Apply CSS styling to the image container (for example, ) Set the width property to the dimension you want For dimensions, use % for relative size, or autoscaling (based on image container or display) Use px (or other) for a static, or set dimension Set the height property to automatically adjust, based on the width ENJOY!

For example,

<img style="width:100%; height:auto;"
    src="https://googledrive.com/host/0BwDx0R31u6sYY1hPWnZrencxb1k/thanksgiving.png"
/>

P
Peter Mortensen

All the provided answers, including the accepted one, work only under the assumption that the div wrapper is of a fixed size. So this is how to do it whatever the size of the div wrapper is and this is very useful if you develop a responsive page:

Write these declarations inside your DIV selector:

width: 8.33% /* Or whatever percentage you want your div to take */
max-height: anyValueYouWant /* (In px or %) */

Then put these declarations inside your IMG selector:

width: "100%" /* Obligatory */
max-height: anyValueYouWant /* (In px or %) */

VERY IMPORTANT:

The value of maxHeight must be the same for both the DIV and IMG selectors.


P
Peter Mortensen

The simplest way to do this is by using object-fit:

<div class="container">
  <img src="path/to/image.jpg">
</div>

.container{
   height: 300px;
}

.container img{
  height: 100%;
  width: 100%;
  object-fit: cover;
}

If you're using Bootstrap, just add the img-responsive class and change to

.container img{
    object-fit: cover;
}

P
Peter Mortensen

If you're using Bootstrap, you just need to add the img-responsive class to the img tag:

<img class="img-responsive" src="img_chania.jpg" alt="Chania">

Bootstrap Images


v
vsync

As seen in my 2014 Codepen example, I've made a solution that would work for any unknown combination of width/height (aspect-ratio) with the help of a as little javascript as possible, to change the CSS of how the image is centered when the aspect-ratio of the container changes above/below the aspect ratio of the image:

Try resizing the container by dragging the bottom right corner:

// Detects when the window width is too narrow for the current image // aspect-ratio, and fits it to height 100% instead of width 100%. const photo = document.images[0] const onPhotoResize = new ResizeObserver(entries => window.requestAnimationFrame(checkRatio) ) onPhotoResize.observe(photo.parentNode) function checkRatio(){ const photoParent = photo.parentNode, imageAspectRatio = photo.clientWidth / photo.clientHeight, parentAspectRatio = photoParent.clientWidth / photoParent.clientHeight photo.classList[imageAspectRatio > parentAspectRatio ? 'add':'remove']('max') } .box{ width: 20%; height: 60%; margin: auto; position: absolute; top:0; left:0; right:0; bottom:0; resize: both; overflow: hidden; border: 5px solid red; } .box > img{ position: absolute; top: 50%; left: 50%; width: 100%; transform: translate(-50%, -50%); } .box > img.max{ width:auto; height:100%; }


P
Peter Mortensen

The solution is easy with a bit of maths...

Just put the image in a div and then in the HTML file where you specify the image. Set the width and height values in percentages using the pixel values of the image to calculate the exact ratio of width to height.

For example, say you have an image that has a width of 200 pixels and a height of 160 pixels. You can safely say that the width value will be 100%, because it is the larger value. To then calculate the height value you simply divide the height by the width which gives the percentage value of 80%. In the code it will look something like this...

<div class="image_holder_div">
    <img src="some_pic.png" width="100%" height="80%">
</div>