HTML Images

HTML Images and Responsive image using the srcset attribute, picture element
Parameters | Details |
---|---|
src | Specifies the URL of the image |
srcset | Images to use in different situations (e.g., high-resolution displays, small monitors, etc) |
sizes | Image sizes between breakpoints |
crossorigin | How the element handles crossorigin requests |
usemap | Name of image map to use |
ismap | Whether the image is a server-side image map |
alt | Alternative text that should be displayed if for some reason the image could not be displayed |
width | Specifies the width of the image (optional) |
height | Specifies the height of the image (optional) |
Creating an image in HTML
To add an image to a page, use the image tag. Image tags (img) do not have closing tags. The two main attributes you give to the img tag are src, the image source and alt, which is alternative text describing the image.
<img src="images/hello.png" alt="Hello World">
You can also get images from a web URL:
<img src="https://i.stack.imgur.com/ALgZi.jpg?s=48&g=1" alt="StackOverflow user Caleb Kleveter">
Note: Images are not technically inserted into an HTML page, images are linked to HTML pages. The <img> tag creates a holding space for the referenced image. It is also possible to embed images directly inside the page using base64:
<img src="data:image/png;base64,iVBOR..." alt="Hello World">
Tip: To link an image to another document, simply nest the <img> tag inside <a> tags.
Choosing alt text in HTML
Alt-text is used by screen readers for visually impaired users and by search engines. It's therefore important to write good alt-text for your images. The text should look correct even if you replace the image with its alt attribute. For example:
<!-- Incorrect -->
<img src="anonymous.png" alt="Anonymous user avatar"/> An anonymous user wrote:
<blockquote>Lorem ipsum dolor sed.</blockquote>
<a href="https://google.com/"><img src="edit.png" alt="Edit icon"/></a> /
<a href="https://google.com/"><img src="delete.png" alt="Delete icon"/></a>
To correct this:
- Remove the alt-text for the avatar. This image adds information for sighted users (an easily identifiable icon to show that the user is anonymous) but this information is already available in the text.1
- Remove the "icon" from the alt-text for the icons. Knowing that this would be an icon if it were there does not help to convey its actual purpose.
<!-- Correct -->
<img src="anonymous.png" alt=""/> An anonymous user wrote:
<blockquote>Lorem ipsum dolor sed.</blockquote>
<a href="https://google.com/"><img src="edit.png" alt="Edit"/></a> /
<a href="https://google.com/"><img src="delete.png" alt="Delete"/></a>
Footnotes
1 There is a semantic difference between including an empty alt attribute and excluding it altogether. An empty alt attribute indicates that the image is not a key part of the content (as is true in this case - it's just an additive image that is not necessary to understand the rest) and thus may be omitted from rendering. However, the lack of an alt attribute indicates that the image is a key part of the content and that there simply is no textual equivalent available for rendering.
Responsive image using the srcset attribute
Using srcset with sizes
<img sizes="(min-width: 1200px) 580px,
(min-width: 640px) 48vw,
98vw"
srcset="img/hello-300.jpg 300w,
img/hello-600.jpg 600w,
img/hello-900.jpg 900w,
img/hello-1200.jpg 1200w"
src="img/hello-900.jpg" alt="hello">
sizes are like media queries, describing how much space the image takes of the viewport.
- if viewport is larger than 1200px, image is exactly 580px (for example our content is centered in container which is max 1200px wide. Image takes half of it minus margins).
- if viewport is between 640px and 1200px, image takes 48% of viewport (for example image scales with our page and takes half of viewport width minus margins).
- if viewport is any other size , in our case less than 640px, image takes 98% of viewport (for example image scales with our page and takes full width of viewport minus margins). Media condition must be omitted for last item.
srcset is just telling the browser what images we have available, and what are their sizes.
- img/hello-300.jpg is 300px wide,
- img/hello-600.jpg is 600px wide,
- img/hello-900.jpg is 900px wide,
- img/hello-1200.jpg is 1200px wide
src is always mandatory image source. In case of using with srcset, src will serve fallback image in case browser is not supporting srcset.
Using srcset without sizes
<img src="img/hello-300.jpg" alt="hello"
srcset="img/hello-300.jpg 1x,
img/hello-600.jpg 2x,
img/hello-1200.jpg 3x">
srcset provides list of available images, with device-pixel ratio x descriptor.
- if device-pixel ratio is 1, use img/hello-300.jpg
- if device-pixel ratio is 2, use img/hello-600.jpg
- if device-pixel ratio is 3, use img/hello-1200.jpg
src is always mandatory image source. In case of using with srcset, src will serve fallback image in case browser is not supporting srcset.
Responsive image using picture element
Code
<picture>
<source media="(min-width: 600px)" srcset="large_image.jpg">
<source media="(min-width: 450px)" srcset="small_image.jpg">
<img src="default_image.jpg" style="width:auto;">
</picture>
Usage
To display different images under different screen widths, you must include all images using the source tag in a picture tag as shown in the above example.
Result
- On screens with screen width >600px, it shows large_image.jpg
- On screens with screen width >450px, it shows small_image.jpg
- On screens with another screen width, it shows default_image.jpg
ATutorialHub Related Guide
HTML Tutorials Comments (9)
User Comments

panduranga gupta
2021-07-05 07:03:13good website for learning and help me a lot

raju
2021-09-25 14:58:47The awsome website i am looking like for a long time, good work atutorialhub team keep doing

Shivani
2021-09-01 15:03:56Learning a lot from the courses present on atutorialhub. The courses are very well explained. Great experience

Harshitha
2021-09-10 15:05:45It is very helpful to students and easy to learn the concepts

Sowmya
2021-09-14 15:06:41Great job Tutorials are easy to understand Please make use of it

Zain Khan
2021-09-18 15:07:23Great content and customized courses.

Rudrakshi Bhatt
2021-09-09 15:08:10Well structured coursed and explained really well!

Pavana Somashekar
2021-09-11 15:09:08Good platform for beginners and learn a lot on this website

Sax
2021-09-25 19:35:50Nice website
Leave a Comment