Why optimize images?
Images play a very important role in search engines and is one of the factors which is generally ignored by many webmasters. Search engines are trying to incorporate more images into SERPs (Search Engine Page Results) and ignoring this could cause you loss of good and sizable traffic. So lets look out all the major factors for implementing ‘SEO for Images’.
- Search engines can detect an image but not the content inside the images which makes it difficult for them to sort out images based on user query.
- With the evolution of Universal Search Results, images have been added to the main page search results in Google resulting into more traffic.
- You must have heard this quote ‘Images speak louder than words‘ so images can help in presenting your content in a more user friendly manner which can help in building your audience.
- Images can also act as link bait if you allow image sharing in exchange of an link.
- Easier sharing with sites like Pinterest getting more popular.
- More Links: According to a recent study by SEOMoz, pages with images get more links than pages without links. Observe the following graph:
How To Optimize?
Now lets get to know the trick for optimizing your images so that they drive maximum traffic to your site.
1) Find right image Finding the right image is half the task done. A good image which attracts attention and describes itself can really do the job for you. So spend time in searching for a good image because it will add a interactive feature in your article which will help you in getting more shares and links. Avoid: Irrelevant images
2) Alt Tags Alt tags displays the text in-case the image is not able to load in the browser helping users to know the details of the image. It not only helps the users but also acts as a base for search engines in identifying what the image contains.
Search engines have got very smart but still they don’t have eyes to know what an image contains. So it is very important to put an alt tag which should be to the point and should contain keywords. For eg: in the above image I have used an alt text as
<img alt="Sunset at Taj mahal" src="http://etechdiary.com/images/taj-mahal-sunset.jpg" />
Avoid: lengthy alt text, keyword stuffing
3) Long descriptions This is a important section which helps you in describing an image in detail helping the search engines to understand it better. This was originally made for the visually impaired but you can use it for optimizing images and provide more information to search engines. It contains a link to a page where the image is described in detail. For eg:
<img alt="Sunset at Taj mahal" src="http://etechdiary.com/images/taj-mahal-sunset.jpg" longdesc="http://etechdiary.com/?attachment_id=978"/>
4) File Name Lets take the example of above picture ‘Taj mahal’. You should give a more descriptive name than just ‘taj-mahal.jpg‘ which is very generic. Instead you could use ‘taj-mahal-at-sunset.jpg’ which is not as generic and can rank good with this name. So choose a name which is related as well as not very generic.
5) File Size FIle size is another important factor for optimizing images. Google considers the page loading time as one of the important factors while ranking which depends on the size of the page (image file size, video size etc). So optimizing images in terms of size can really improve your site performance. File size depends on the resolution of the image, more the resolution more is the size. So you need to maintain a balance between the size and the quality. There are different image types supported on web and most common ones are:
- JPG: It is the most commonly used method with adjustable degree of compression. When JPG files are saved, they use “lossy” compression, meaning image quality is lost as file size decreases. JPEG typically achieves 10:1 compression with little perceptible loss in image quality. Can support 16 million colors.
- PNG: It uses “lossless compression”, meaning no loss in quality of image. It is mostly used in case where transparency is required which is not supported by jpg. It was created as an replacement of GIF. File size is a bit higher than JPG. It also supports 16 million colors.
- GIF: It supports animation in images so mostly used for the same. It also includes data compression, but because it is limited to 256 colors, it is more effective for scanned images such as illustrations rather than color photos.
It is very difficult to choose the best and the optimal from one of these as it completely depends on your requirement. Try and choose a image which is of good quality and lowest file size. In case you are confused in selecting the image, do go for different variations for trial and select the best one.
Avoid: Very high resolution images, do not reduce image size by html tags (like width and height because it takes the same space)
6) Anchor Text Anchor text are the links linking to an image. Suppose you have a link “Taj Mahal” linking to the its image then using a descriptive text can provide useful information to the search engines. Do use random characters with the keywords for an effective result.
7) Surrounding Content Search engines also consider the content surrounding the image. Whenever a search engine detects an image it starts crawling surrounding content to get more information about it. So use related content and images with a proper variation of keywords (or you can also use synonyms of keywords)
8) Image Sitemap The image sitemap has the same purpose as the web pages sitemap. It helps in indexing your images in search engine directory. Creating a sitemap can be really helpful and you can go through following links for details:
9) Rich Snippets You can also have rich snippets for you site so that your image is shown in search results. Having a picture in search results definitely improves the click through rate. So its a good concept to implement. You can learn this trick ofro here “Display picture in Google Search“.
10) Geo Location Geo Location refers to the localized search results. It means that in the above example of “Taj-Mahal”, we could use “Agra-Taj-Mahal” as the file name which will help you in getting good position in localized search results.
Things to keep in mind
Some features are not very important as individual but if you apply all the optimization methods as a whole it will take your image results to a different level all together.
1) Use keywords in file name, alt tags and image description.
2) Don’t stuff keywords. Use it intelligently (like use of synonyms)
3) Tell as much as possible about the image. 4) Do not ignore user experience (it is very important)