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SEO for Images: Best 11 Tips to Optimize Images

February 12, 2019


It can be easy for companies to overlook some of the smaller steps towards good on-site SEOs, but anything that you can do to strengthen the SEO of your website makes a difference. SEO includes a lot of different factors. To make your web site more competitive on search engines, taking time to optimize your image for SEO is a simple and important step.

What is image optimization?

Image optimization involves minimizing your images' file size without compromising quality, so that loading time is low on your webpages. This means that Google and other image search engines rank your product depending on the quality and optimization of the images.

Why Images Are Important for SEO?

We understand SEO in many respects, but forget that optimization of images is also important like quality content and keywords. Firstly, good and optimized images, for user experience, are extremely important. Think about it: you would not feel like a trustworthy or memorable website if you were to be on its webpage that looked like a Word doc with nothing but a White background text. Indeed, research confirms that 80% more people read content that contains an image and 64% revisit it afterwards.

Images are a large part of the way a web page lives. This is important for SEO, as Google's algorithm reports behavior metrics which reflect the user experience, such as bounce rates and time spent on a web page. But pictures can be optimized to help SEO more directly as well. If the average visitor to your page only sees the picture, the search engine crawlers will see text behind the image to tell you what they are looking for.

 Best 11 Tips to Improve Your SEO for Images

Follow these tips to optimize images for search engines:

1.Use relevant, high-quality images


This is important for SEO and better user experience. A picture not related to the content of the webpage will make your blog look bad, unprofessional and confusing for the user. Check that each image you use has a clear link to and looks good on the page. You have to be careful not to use any plagiarized images i.e., to which you have no rights. You can find plenty of resources online which allow using copyright free images. Get time to find at least one good and un-plagiarized image.

2.Customize the filename

This is step is so incredibly easy but not one does it. Take time to customize the filename before adding an image to your website. Change it to something relevant to your page and include one of your focus keywords. The pictures can be given the name something like brandname-prepostseo.jpg, if it is about an SEO tool. Most visitors will never see the filename, but it provides information to the search engines that what is on this page and what are the best keywords that can be associated with your site.

3.Use alt tags

This is yet another section of the website that is not visited by visitors but by search engine crawlers. If a browser finds it difficult to load, you can provide alt text for each of the pictures to add to your site. Using alt tags is another technique which you can use to indicate what the page is about to indicate search engines. Always update your images with the alt text. Enter your main page keyword and something that describes the image itself. You can write it in if you are using WordPress with an alt text field.

4.Find the right quality-to-size ratio

This part is a bit difficult and tricky because your images need to be content relevant, appealing and of better resolution, but you don't want images big enough to slow down your website. Site speed is a SEO ranking factor and it is bad for the user experience and SEO if your visitors have to wait a while until their page is loaded. Often the image file size is much larger than it needs to appear on your website. If you are using a CMS such as WordPress, it is super easy to resize the size of your website image after loading it to CMS–but you still may have the large file that slows down the webpage.

By resizing your image files before you upload them, you can speed up your web site while still showing high-resolution images. This is often easy on most computers, like Mac's Preview program or Microsoft Paint, programs which are standard built in software designed to perform such tasks. Either you can use the command "Saving for Web" if you have Adobe Photoshop to locate the smallest file size which still provides a satisfactory resolution. After you resize, the picture file size can still be reduced by compressing it without losing its quality. To facilitate this process, you can use tools such as TinyPNG and JPEGmini.

5. Choose the right file type.

You may have noticed that there are three main types of images, but you may not really realize the difference. Understanding the file types can help you select the one that best meets your requirements:


JPG is one of the most common file formats since it is widely supported in small file sizes. But the quality of the picture isn't always as good as with PNG files and the format isn't clear, so sometimes JPG will not work. PNG is a high-resolution image file format that supports a text image description and good for SEO. It tends to be larger than JPG and GIF, which is the major downside of PNG. For complex pictures and those with text, it's often best. GIF does not support a color range as broad as the other two, but for simple pictures it can be a good choice. It supports small sizes of file and transparent contexts.

JPG often works well for photos. GIF and PNG are more common for designed graphics, and PNG is the way to get a better quality version.

5.Add images to your sitemap

Google crawls your pages better and add them to the index when you submit a sitemap. You can also include images into your map or create a separate image sitemap to submit alternatively. You can use plug-ins if you are using WordPress, such as Google XML Sitemap for Images, and Undira All Image Sitemap, to generate a picture sitemap for you. By providing clear image information on Google's website, you increase the chance of Google image search, which increases the overall ability of your website to be found and eventually your site rank.

If you use Javascript gallery, "flashy" and pop-up images will be noticeable by Google only if you add images to your sitemap. Web crawlers are unable to crawl images which are not specifically called in the source webpage. Therefore you have to list the location on an image map to inform crawlers about unidentified images. In your robots.txt file, the following line can be inserted, showing the path to your site map: http:/xyzexample.com/sitemap.xml, or you can send sitemap using Search Console to Google. Google has many image publication guidelines that may enhance the SERP status of your website. You can also use Google mapping to provide Google with more information about the pictures of your website, which will enable Google to find more than its own. Sitemaps don't guarantee Google's indexing of your images, but it is definitely a positive step towards image SEO. There are many tips for correctly formatting your sitemap for Google Webmaster Tools. For all your images it is important to add specific tags. A separate sitemap can also be created to list only images on sitemap. The important thing is to add all the necessary information to any sitemaps you have or create while using specific tags.

7. Host images on your own site

While hosting your image on other websites can be tempting to save space but that’s a real risk. Whenever the traffic on these sites is overloaded, your images could not load, create a confusing experience on your website and make your brand look bad.

Host the pictures on your website and make your picture-file size smaller to make it not slower than necessary to your web pages. And you will always know how your images (as well as the rest of your site) appear as they are for your visitors when you go with a reliable hosting provider.

8. Beware of decorative images

Websites usually have a variety of decorative images, including background images, buttons and borders. Anything related to non-products can probably be seen as a decorative picture. While decorative images can make a web page more esthetic and attractive, they can cause a large file size and slow loading times. Therefore, you may wish to examine your decorative pictures more closely so that they do not damage your visitor-converting ability to your web site.

Some tips for reducing the file size of your decorative images are given below: Make PNG-8 or GIF for images which have borders or simple patterns. You can create look-alike images of just a few hundred bytes. Use CSS instead of using pictures to create colored areas. To replace any decorative images, use as much CSS styling as possible. And minify css file. There could be multiple files. Resize them without ruining the image quality as much as possible.

9. Optimize thumbnail

Many e-commerce sites, particularly on category pages, will use images from thumbnails. Without overtaking space, they rapidly display products. The thumbnails are great, but beware; they can be a silent killer. Who will be the victim? The load speeds of your page. In critical points in the shopping process thumbnails are usually presented. You could lose a potential customer if you prevent your category pages from loading rapidly. So, what are you capable of doing? Make sizes as small as possible for your thumbnail. You can keep a slide of quality to a lower size of the file. Remember, your thumbnails have huge cumulative effects on the loading time of your page. Change your alt text attribute not to duplicate text for the larger versions of the same picture. Actually, make your alt text different wildly. The last thing you want is to index the thumbnail rather than the bigger image. The alt text could be entirely the reason for indexing thumbnails of the site get indexed.

10. Add captions

Captions can be crawled through search engines spiders, like URLs. If you use your caption related to your keywords, search results will list your page on top. The key is to maintain the relevance of both the page and the image. Title Images with misleading tags will drive your bounce rate faster and send Google's search engine poor signals that your content does not match correctly. In addition, the captions make your content more attractive and easier for readers to understand. KissMetrics says that the picture captions are 300 percent higher on average than the body copy itself. Leaving images without captions can harm SEO and user experience.

11. Test Images

The whole point of optimizing your pictures is to help you to improve your results. We have been talking about file size reduction and search engines to index your images, but what about images testing to see what is turned into more customers?

Test the number of product pictures per page: Since loading times are a problem for certain non-host ecommerce sites, reduction in the number of images on a page increases clicking through rates and sales. It is possible to improve user experience and lead to more sales by providing lots of pictures per page. Testing is the only way to find out.

Test what angles your customers want: By giving your customers a desired view you may see the rise in customer loyalty. One great way to understand this is to examine your customers what they really loved when they saw your product shots. It's a good habit to survey and talk to your customers in general.

Test how many product lists on the category pages you should have: 10, 20 or 100? To verify what work’s best for your customers, test the number of products you list on category pages.


As far as SEO is concerned, image SEO is relatively easy. You can give your pages an extra edge in the search engines by spending some time, finding and optimizing the right images for searching each time you add a page to your website.