JavaScript Find Real Image Width and Height

How to Get Image Size Using JavaScript

You can get the original width and height of an image using the HTML5 image naturalWidth and naturalHeight properties, which are supported in almost all major browsers.

html> html> head> title>Title of the Document title> head> body> div>Click on img to see the result div> script> let img = document.createElement('img'); img.id = 'imgId'; img.src = '/uploads/media/default/0001/05/e9f3899d915c17845be51e839d5ba238f0404b07.png'; document.body.appendChild(img); img.addEventListener("click", imgSize); function imgSize( ) < let myImg = document.querySelector("#imgId"); let realWidth = myImg.naturalWidth; let realHeight = myImg.naturalHeight; alert("Original width=" + realWidth + ", " + "Original height=" + realHeight); > script> body> html>

To get the current width and height, you can use the JavaScript clientWidth and clientHeight properties. These are DOM properties that show the current in-browser size of the inner dimensions of a DOM element, excluding margin and border.

html> html> head> title>Title of the Document title> style> img < margin: 20px; > style> head> body> div>Click on img to see the result div> script> let img = document.createElement('img'); img.id = 'imgId'; img.src = 'https://pbs.twimg.com/profile_images/1144166476682813440/o23kohmr_400x400.png'; document.body.appendChild(img); img.addEventListener("click", imgSize); function imgSize( ) < let img = document.getElementById('imgId'); //or however you get a handle to the IMG let width = img.clientWidth; let height = img.clientHeight; alert("Original width=" + width + ", " + "Original height=" + height); > script> body> html>

The naturalWidth and naturalHeight Properties

The naturalWidth and naturalHeight are read-only properties that return the original width and height of an image, respectively. As the width and height of an image displayed on the webpage can be altered using the ‘width’ and ‘height’ attributes of the tag, the naturalWidth and naturalHeight properties are used in situations where original width or height of the image is required.

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How to get original image size (width & height) in JavaScript

Answer: Use the HTML5 naturalWidth and naturalHeight

You can easily find the original or intrinsic width and heigh of an image using the HTML5 image naturalWidth and naturalHeight properties. These properties are supported in all major web browsers such as Chrome, Firefox, Safari, Opera, Internet Explorer 9 and above.

Let’s take a look at an example to understand how it basically works:

Example

     function imgSize()  Cloudy Sky

Alternatively, if you want to perform the same task with jQuery you can use the load() method in combination with the attr() method, as shown in the following example:

Example

         Cloudy Sky

Here are some more FAQ related to this topic:

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HTML Images

Images can improve the design and the appearance of a web page.

Example

Italian Trulli

Example

Girl in a jacket

Example

Flowers in Chania

HTML Images Syntax

The HTML tag is used to embed an image in a web page.

Images are not technically inserted into a web page; images are linked to web pages. The tag creates a holding space for the referenced image.

The tag is empty, it contains attributes only, and does not have a closing tag.

The tag has two required attributes:

Syntax

The src Attribute

The required src attribute specifies the path (URL) to the image.

Note: When a web page loads, it is the browser, at that moment, that gets the image from a web server and inserts it into the page. Therefore, make sure that the image actually stays in the same spot in relation to the web page, otherwise your visitors will get a broken link icon. The broken link icon and the alt text are shown if the browser cannot find the image.

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Example

Flowers in Chania

The alt Attribute

The required alt attribute provides an alternate text for an image, if the user for some reason cannot view it (because of slow connection, an error in the src attribute, or if the user uses a screen reader).

The value of the alt attribute should describe the image:

Example

Flowers in Chania

If a browser cannot find an image, it will display the value of the alt attribute:

Example

Tip: A screen reader is a software program that reads the HTML code, and allows the user to «listen» to the content. Screen readers are useful for people who are visually impaired or learning disabled.

Image Size — Width and Height

You can use the style attribute to specify the width and height of an image.

Example

Girl in a jacket

Alternatively, you can use the width and height attributes:

Example

Girl in a jacket

The width and height attributes always define the width and height of the image in pixels.

Note: Always specify the width and height of an image. If width and height are not specified, the web page might flicker while the image loads.

Width and Height, or Style?

The width , height , and style attributes are all valid in HTML.

However, we suggest using the style attribute. It prevents styles sheets from changing the size of images:

Example

Images in Another Folder

If you have your images in a sub-folder, you must include the folder name in the src attribute:

Example

Images on Another Server/Website

Some web sites point to an image on another server.

To point to an image on another server, you must specify an absolute (full) URL in the src attribute:

Example

W3Schools.com

Notes on external images: External images might be under copyright. If you do not get permission to use it, you may be in violation of copyright laws. In addition, you cannot control external images; they can suddenly be removed or changed.

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Animated Images

HTML allows animated GIFs:

Example

To use an image as a link, put the tag inside the tag:

Example

Image Floating

Use the CSS float property to let the image float to the right or to the left of a text:

Example

The image will float to the right of the text.

The image will float to the left of the text.

Tip: To learn more about CSS Float, read our CSS Float Tutorial.

Common Image Formats

Here are the most common image file types, which are supported in all browsers (Chrome, Edge, Firefox, Safari, Opera):

Abbreviation File Format File Extension
APNG Animated Portable Network Graphics .apng
GIF Graphics Interchange Format .gif
ICO Microsoft Icon .ico, .cur
JPEG Joint Photographic Expert Group image .jpg, .jpeg, .jfif, .pjpeg, .pjp
PNG Portable Network Graphics .png
SVG Scalable Vector Graphics .svg

Chapter Summary

  • Use the HTML element to define an image
  • Use the HTML src attribute to define the URL of the image
  • Use the HTML alt attribute to define an alternate text for an image, if it cannot be displayed
  • Use the HTML width and height attributes or the CSS width and height properties to define the size of the image
  • Use the CSS float property to let the image float to the left or to the right

Note: Loading large images takes time, and can slow down your web page. Use images carefully.

HTML Exercises

HTML Image Tags

Tag Description
Defines an image
Defines an image map
Defines a clickable area inside an image map
Defines a container for multiple image resources

For a complete list of all available HTML tags, visit our HTML Tag Reference.

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