They say – 'A picture is worth a thousand words'. This is true! But is it from a SEO perspective? Not really. While carefully placed images can increase conversion and make the page look better, it doesn't benefit SEO as such. Search Engines cannot easily crawl and understand the images. This makes it quite impossible for a search engine to rank a website for relevant keywords if the website only has a few images and not enough text content. This is where Image ALT tags can help.
What are Image ALT tags?
ALT is short for 'alternative'. It is an attribute used in HTML/XHTML documents. It is used for rendering suitable and relevant text when an associated object is unable to be rendered. The Image ALT tag is used for specifying image description when a website is unable to display the image due to low bandwidth or incompatible device. It is also important to understand that ALT tag need not always describe the image. Think of it as an alternative text that would provide useful information for someone who would not be seeing the image.
Importance of ALT tags in SEO
Since search engine bots are unable to understand the images well, the image alt tags are used by them for identifying the images. SE bots read the Image ALT tags and get an idea of the image. It further helps SE bots to comprehend and relate the content to apt search queries. This means that with proper use of image ALT tag, you can –
- improve your webpage's keyword relevance
- increase search engine visibility by getting your images indexed for search queries
What does an Image ALT tag code look like?
A simple image ALT tag would look like something below –
<img alt="this is where you write the alternaive text" src="http://your domain.com/yourimage.jpg">
How to properly implement image ALT tag?
Be natural and descriptive. A good idea is to use 3-8 words of description as your alt text. Adding your keyword to the image ALT tag is also good. However, attention is to be paid that you add the keywords naturally and do not stuff the keywords. Also ensure that you do not use the same keyword-rich image Alt text over and over. Google is smart and can easily flag any attempt to manipulate SERPs.
Let us do a quick example to better understand the use of image ALT tag. Say you have an image of a plumber as depicted below –
Now if you are going to use it on a website whose main target keyword-phrase is 'New York plumber' then here are some possible image ALT tags you can use –
- New York plumber (3 words and comprising only keyword)
- plumber working in New York (5 words reflecting the keyword)
- a plumber working on a job in New York (descriptive, 9 words reflecting the keyword)
- a guy performing plumbing job in New York (descriptive, keyword-oriented)
Either of these would work. As long as you have an ALT tag that is keyword-oriented (contains or reflects your keyword in exact or seantic form), you are good.
How To Check Images For ALT tags optimization?
While you can always look at the source code of a webpage to see if they are missing image ALT tags, but that's not very cool and informative. Since I need to do this on a regular basis (when auditing websites), I rely on a more professional and accurate means. Thanks to Patrick Sexton for creating a nifty utility over at FeedTheBot that helps you analyze all images on a webpage. It not only tells about the use of image ALT text with your images but also about some other crucial image optimization details.
Analyze your webpages/blog posts now and ensure that you use a relevant and keyword-oriented image ALT tag. Feel free to ping me should you have any questions.