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Summary
The HTML <img>
element represents an image in 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 cannot 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.
Content categories | Flow content, phrasing content, embedded content, palpable content. If the element has a usemap attribute, it also is a part of the interactive content category. |
---|---|
Permitted content | None, it is an empty element. |
Tag omission | Must have a start tag and must not have an end tag. |
Permitted parent elements | Any element that accepts embedded content. |
DOM interface | HTMLImageElement |
Attributes
This element includes the global attributes.
align
Deprecated since HTML4.01, Obsolete since HTML5- The alignment of the image with respect to its surrounding context. In HTML5, use the
float
and/orvertical-align
CSS properties instead. alt
- This attribute defines the alternative text describing the image. Users will see this text 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 altogether indicates that the image is a key part of the content, and no textual equivalent is available. Setting this attribute to an empty string (
alt="")
indicates that this image is not a key part of the content, and that non-visual browsers may omit it from rendering. border
Deprecated since HTML4.01, Obsolete since HTML5- The width of a border around the image. In HTML5, use the
border
CSS property instead. 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 theAccess-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 (throughAccess-Control-Allow-Credentials:
HTTP header), the image will be tainted and its usage restricted.
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 pixels. In HTML 4, the height could be defined pixels or as a percentage. In HTML5, however, the value must be in pixels.
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. In HTML5, use the
margin
CSS property instead. 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.
longdesc
- A link to a more detailed description of the image. Possible values are a URL or an element id.
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. referrerpolicy
- A string indicating which referrer to use when fetching the resource:
no-referrer:
theReferer
header will not be sent.no-referrer-when-downgrade:
noReferer
header will be sent when navigating to an origin without TLS (HTTPS). This is a user agent’s default behavior if no policy is otherwise specified.origin:
theReferer
header will include the page of origin's scheme, the host and the port.origin-when-cross-origin:
navigating to other origins will limit the included referral data to the scheme, the host and the port, while navigating from the same origin will include the referrer's full path.unsafe-url:
theReferal header
will include the origin and the path, but not the fragment, password or username. This case is unsafe because it can leak origins and paths from TLS-protected resources to insecure origins.
sizes
HTML5- A list of one or more strings separated by commas indicating a set of source sizes. Each source size consists of:
- a media condition. This must be omitted for the last item.
- 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 thesrcset
attribute is absent, or contains no values with a width (w
) descriptor, then thesizes
attribute has no effect. src
- The image URL. This attribute is mandatory for the
<img>
element. On browsers supportingsrcset
,src
is treated like a candidate image with a pixel density descriptor1x
unless an image with this pixel density descriptor is already defined insrcset,
or unlesssrcset
contains 'w
' descriptors. srcset
HTML5- 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:
- a URL to an image,
- optionally, whitespace followed by one of:
- a width descriptor, or a positive integer directly followed by '
w
'. The width descriptor is divided by the source size given in thesizes
attribute to calculate the effective pixel density. - a pixel density descriptor, which is a positive floating point number directly followed by '
x
'.
- a width descriptor, or a positive integer directly followed by '
If no descriptor is specified, the source is assigned the default descriptor:
1x
.It is incorrect to mix width descriptors and pixel density descriptors in the same
srcset
attribute. Duplicate descriptors (for instance, two sources in the samesrcset
which are both described with '2x
') are invalid, too.The user agent selects any one of the available sources at its discretion. 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 pixels. In HTML 4, either a percentage or pixels were acceptable values. In HTML5, however, only pixels are acceptable.
usemap
- The partial URL (starting with '#') of an image map associated with the element.
vspace
Deprecated since HTML4.01, Obsolete since HTML5- The number of pixels of white space to insert above and below the image. In HTML5, use the
margin
CSS property instead.
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:
Interaction with CSS
Regarding CSS, <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 placed on the container's baseline.
Depending on its type, an image may have an intrinsic width and height. For some image types, however, intrinsic dimensions are not necessary. SVG images, for instance, have no intrinsic dimensions.
Example 1: Alternative text
<img src="mdn-logo-sm.png" alt="MDN">
Example 2: Image link
<a href="https://developer.mozilla.org/">MDN<img src="mdn-logo-sm.png" alt="MDN"></a>
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 |
---|---|---|
Referrer Policy The definition of 'referrer attribute' in that specification. |
Working Draft | Added the referrerpolicy attribute. |
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 | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
srcset |
34.0 | (Yes) | 32.0 (32.0)[2] | No support | 21 | 7.1 |
referrerpolicy |
46.0[1] | ? | 50.0 (50.0) | ? | ? | ? |
Feature | Android | Android Webview | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile | Chrome for Android |
---|---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
srcset |
? | 34.0 | No support | No support | 21 | iOS 8 | 34.0 |
referrerpolicy |
? | 46.0 [1] | 50.0 (50.0) | ? | ? | ? | 46.0[1] |
[1] Implemented as referrerpolicy
and behind a flag.
[2] Implemented behind a preference.