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    <img>

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    Summary

    The HTML Image Element (<img>) represents an image of the document.

    Usage note:
    Browsers do not always display the image referenced by the element. This is the case for non-graphical browsers (including those used by people with vision impairments), if the user chooses not to display images, or if the browser is unable to display the image because it is invalid or an unsupported type. In these cases, the browser may replace the image with the text defined in this element's alt attribute.

    Attributes

    This element includes the global attributes.

    align Deprecated since HTML4.01, Obsolete since HTML5 Use the vertical-align CSS property
    The alignment of the image with respect to its surrounding context.
    alt
    This attribute defines the alternative text describing the image. Users will see this displayed if the image URL is wrong, the image is not in one of the supported formats, or if the image is not yet downloaded.

    Usage note: Omitting this attribute indicates that the image is a key part of the content, but no textual equivalent is available. Setting this attribute to the empty string indicates that this image is not a key part of the content; non-visual browsers may omit it from rendering.

    border Deprecated since HTML4.01, Obsolete since HTML5
    The width of a border around the image.
    crossorigin HTML5
    This enumerated attribute indicates if the fetching of the related image must be done using CORS or not. CORS-enabled images can be reused in the <canvas> element without being tainted. The allowed values are:
    anonymous
    A cross-origin request (i.e., with Origin: HTTP header) is performed. But no credential is sent (i.e., no cookie, no X.509 certificate, and no HTTP Basic authentication is sent). If the server does not give credentials to the origin site (by not setting the Access-Control-Allow-Origin: HTTP header), the image will be tainted and its usage restricted.
    use-credentials
    A cross-origin request (i.e., with Origin: HTTP header) performed with credential is sent (i.e., a cookie, a certificate, and HTTP Basic authentication is performed). If the server does not give credentials to the origin site (through Access-Control-Allow-Credentials: HTTP header), the image will be tainted and its usage restricted.
    When not present, the resource is fetched without a CORS request (i.e., without sending the Origin: HTTP header), preventing its non-tainted usage in <canvas> elements. If invalid, it is handled as if the enumerated keyword anonymous was used. See CORS settings attributes for additional information.
    height
    The intrinsic height of the image in HTML5 CSS pixels, or HTML 4 in pixels or as a percentage.
    hspace Deprecated since HTML4.01, Obsolete since HTML5
    The number of pixels of white space to insert to the left and right of the image.
    ismap
    This Boolean attribute indicates that the image is part of a server-side map. If so, the precise coordinates of a click are sent to the server.

    Usage note: This attribute is allowed only if the <img> element is a descendant of an <a> element with a valid href attribute.

    longdescHTML 4 only
    The URL of a description of the image to be displayed, which supplements the alt text. In HTML5, use a regular <a> element to link to the description.
    name Deprecated since HTML4.01, Obsolete since HTML5
    A name for the element. It is supported in HTML 4 only for backward compatibility. Use the id attribute instead.
    sizesHTML5
    A list of one or more strings separated by commas indicating a set of source sizes. Each source size consists of:
    1. a media condition. This must be omitted for the last item.
    2. a source size value.

    Source size values specify the intended display size of the image. User agents use the current source size to select one of the sources supplied by the srcset attribute, when those sources are described using width ('w') descriptors. The selected source size affects the intrinsic size of the image (the image’s display size if no CSS styling is applied). If the srcset attribute is absent, or contains no values with a width descriptor, then the sizes attribute has no effect.

    src
    The image URL. This attribute is mandatory for the <img> element. On browsers supporting srcset, src is treated like a candidate image with a pixel density descriptor 1x unless an image with this pixel density descriptor is already defined in srcset or srcset contains 'w' descriptors.
     
    srcsetHTML5
    A list of one or more strings separated by commas indicating a set of possible image sources for the user agent to use. Each string is composed of:
    1. a URL to an image,
    2. optionally, whitespace followed by one of:
      • a width descriptor, that is a positive integer directly followed by 'w'. The width descriptor is divided by the source size given in the sizes attribute to calculate the effective pixel density.
      • a pixel density descriptor, that is a positive floating point number directly followed by 'x'.

    If no descriptor is specified, the source is assigned the default descriptor: 1x.

    It is invalid to mix width descriptors and pixel density descriptors in the same srcset attribute. Duplicate descriptors (for instance, two sources in the same srcset which are both described with '2x') are invalid, too.

    User agents are given discretion to choose any one of the available sources. This provides them with significant leeway to tailor their selection based on things like user preferences or bandwidth conditions.

    width
    The intrinsic width of the image in HTML5 CSS pixels, or HTML 4 in pixels or as a percentage.
    usemap
    The partial URL (starting with '#') of an image map associated with the element.

    Usage note: You cannot use this attribute if the <img> element is a descendant of an <a> or <button> element.

    vspace Deprecated since HTML4.01, Obsolete since HTML5
    The number of pixels of white space to insert above and below the image.

    Supported image formats

    The HTML standard doesn't give a list of image formats that must be supported, so each user agent supports a different set of formats. Gecko supports:

    Note:
    Support for the XBM format has been removed in Gecko 1.9.2.

    Interaction with CSS

    Regarding CSS, an <img> is a replaced element. It has no baseline, so when images are used in an inline formatting context with vertical-align: baseline, the bottom of the image will be posed on the container's baseline.

    Depending on its type, an image may have an intrinsic width and height, but will not necessarily have them. For instance, SVG images have no intrinsic dimensions.

    Example 1

    <img src="mdn-logo-sm.png" alt="MDN">
    

    MDN

    <a href="https://developer.mozilla.org/"><img src="mdn-logo-sm.png" alt="MDN"></a>

    MDN

    Example 3: Using the srcset attribute

    The src attribute is a 1x candidate in user agents that support srcset.

     <img src="mdn-logo-sm.png" 
          alt="MDN" 
          srcset="mdn-logo-HD.png 2x">

    Example 4: Using the srcset and sizes attributes

    The src attribute is ignored in user agents that support srcset when using 'w' descriptors. When the (min-width: 600px) media condition matches, the image will be 200px wide, otherwise it will be 50vw wide (50% of the viewport width).

     <img src="clock-demo-thumb-200.png" 
          alt="Clock" 
          srcset="clock-demo-thumb-200.png 200w, clock-demo-thumb-400.png 400w"
          sizes="(min-width: 600px) 200px, 50vw">

    Specifications

    Specification Status Comment
    WHATWG HTML Living Standard
    The definition of '<img>' in that specification.
    Living Standard  
    HTML5
    The definition of '<img>' in that specification.
    Recommendation  
    HTML 4.01 Specification
    The definition of '<img>' in that specification.
    Recommendation  

    Browser compatibility

    Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    srcset attribute 34.0 32.0 (32.0) (behind a pref) Not supported 21 7.1
    Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
    Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
    srcset attribute Chrome 34 Not supported Not supported 21 iOS 8

    See also