What is Alt Image Text?
Alt text for images, also known as alt tags, provides alternative text to describe images on web pages. Alt text is important to provide additional information when the image cannot be viewed. It also helps people with accessibility requirements and search engines understand the image.
Example of Alt Text Code for Images
Below is an example of the HTML image alt tag displayed in the code of a web page:
<img alt = "Example of anchor text for internal links." src = "https://www.tomdonohoe.com.au/wp-content/uploads/2019/05/anchor-text-example.jpg">
Why is Alt Text for Images Important?
Alt text for images is important because it makes images accessible to people with visual impairments and can also assist with image SEO.
Let's delve into these topics.
Accessibility
Alt text for images is crucial to ensure that images can be used by people with various disabilities.
Some cases where alt text is used for accessibility:
- People using screen readers
- People using speech input software
- People browsing speech-driven websites
- Search engines
An example from Wikipedia:
The alt attribute is used by "screen reader" software so that a person who is listening to the content of a webpage (for instance, a person who is blind) can interact with this element.
SEO for Images
If you want your images to rank on Google Images, alt text for images is an important signal for Google. John Muller from Google emphasized this point on Twitter:
Alt text is extremely helpful for Google Images — if you want your images to rank there. Even if you use lazy-loading, you know which image will be loaded, so get that information in there as early as possible & test what it renders as.John Muller
Apart from Google Images, alt text can add additional relevance signals to the content on your page and help improve rankings on Google.
How to Write SEO-Friendly Alt Text for Your Images
Alt text for images is not only a great opportunity to enhance the user experience but also your on-page SEO. Let's take a look at some practical tips you can follow.
Be Concise and Descriptive
Your alternative text should be read as if you are explaining the image in a concise sentence to a friend over the phone. Read your image alt tag aloud and see if it makes sense.
Don't write paragraphs to explain the image. One sentence is more than enough.
Include Your Primary Keyword When Possible
Write alt text for images that includes your target keyword in the natural flow of the sentence. This can help the image rank well on Google Images and also improve the ranking of your current pages.
Don't stuff all your keywords in the alt text of the image or provide context for what the image is about. Google will simply ignore it.
Give Images a Relevant File Name
When uploading images, remember to give them a relevant file name instead of '65416541.jpg'. Also, try to include your keyword in the file name. For example, if your image is of a training room, make the alt text 'training-room.jpg'.
Don't give files overly long names. 3-5 words are more than enough.
Examples of Good and Bad Alt Text for Images
Alt text for images is easily done well if you take the time to create a sentence that helps users and search engines.
Imagine the above image is on the landing page of a website targeting the phrase 'yogales':
Bad alt text:
<img src="yoga.png" alt="yoga class">
Okay alt text:
<img src="yoga.png" alt="women doing a yoga class">
Great alt text:
<img src="yoga.png" alt="group of fit women doing a yoga class in active clothing.">
