What is image optimization?

Image optimization is a part of SEO or Search Engine Optimization. To rank your contents in Google and other search engines, you need to write texts maintaining some ground rules. In the same way, if you want the product images of your e-commerce site to come to a higher position in image search engines, you must follow some techniques too. Such techniques are called image optimization.

Why Do You Need Image Optimization?

Do you own an e-commerce site? Are you working on Amazon affiliate program? Do you have blogs that are full of special kinds of pictures? You must optimize your pictures on the web along with the textual contents to rank those sites properly People nowadays search for products in the image search option of search engines, then they click on their desired picture to see which site has it. So you must try to do something to keep your pictures at the top portion of the image search result page. Also, image optimization is related to ranking your page contents and reducing page load time.

10 Must Know Image Optimization Tips

There is no end to learning and efforts. But in order to make you aware of the basic image optimization techniques, here we have made a list of 10 essential tips that must be known to all e-commerce site owners or bloggers. Feel free to ask us anything if you cannot understand something.

1. Relevant and Descriptive Image File Name in Plain English

You must create or choose descriptive and keyword-rich file names before uploading the images to your site. Names of image files have great value to Google and other search engine crawlers because they understand the content of the images with the help of filenames that you provide.

When you take a picture from a camera, it generates file names such as DCIM_2319, IMG_556 etc. Do you think this names will help you with the SEO? So you must change the name to a relevant and descriptive name of the product. For example, if it is a picture of a power bank, the name can be:

Xiaomi 10000mah Power Bank White

Xiaomi Power Bank White 10000mah

The keyword patterns also need to be chosen wisely with help of AdWords and SEO.

2. Write SEO-friendly Alt Attributes

When a browser cannot render an image properly, Alt tags or attributes act as alternatives to those images by showing the viewer some texts inside the image box about the content of that picture. This is very important among the 10 must know image optimization tips which we are discussing now. You need to make sure if the Alt text fits with the image box. Also, add relevant information in the text such as model number, serial number, edition, color etc. Never write Alt attributes for decorative images, if you do that, search engines might penalize you.

3. Reduce Image Size

Larger images affect your page load time. Customers may get disappointed and close the tab if they keep waiting for their desired product images to complete loading fully. This can be counted as a bounce, and it is not good for SEO. Using “Save for Web” option from the Photoshop can give you the optimal size of a picture without losing the details or quality. There is also several software for compressing images such as GIMP, Canva, PIXLR, PicMonkey etc.

4. Mange Image Dimensions and Product Angles

Depending on the angle and dimensions you need to change your alt tags and file names accordingly. For example, if your product is a car, you can add the words such as interior, front, back etc. in the alt tags and file names for the images taken in such angles. If you take pictures of engine, wheels, doors etc. particularly, you should also mention the name in the caption, file name, and alt tags.

5. Thumbnail Optimization

Make the sizes of your thumbnail files as small as possible. Don’t hesitate to do it even if their picture quality decreases. Keep in your mind that thumbnails affect your page load time.

Do not use the same alt tag/attribute text in thumbnail images that you used for real/bigger images. Do you want your thumbnail images indexed instead of the big product images? If not, then you can avoid using alt text for thumbnail images totally.

6. Use Suitable File Types

You can lower the size of your images and decrease the page load time by using particular file types for particular areas: JPEG, PNG, and GIF.

JPEGs should be file type of your main product images. They offer the best quality and details despite having a smaller file size. For big product images, never use GIFs.

The file size of GIFs is larger and you won’t be able to reduce it at all. You can use this format for small images or images that have a smaller file size. The best use of GIFs is for decorative images and thumbnails and only.

PNGs are the best alternative to JPEGs and GIFS. This is a format that you can avail after going through Photoshop. Try using PNG-8 instead of PNG-24 if you can manage product images in PNGs. Their file size is small and they don’t degrade over resaving.

7. Be Careful About Decorative Images

Here, by the word ‘decorative’ we mean all images on your site that are not related to products. Those may be borders, arrows, signs, designs, buttons etc. Since those are images, they also have a huge impact on the page load time. Use the following tricks to optimize them:

For images of patterns and borders, convert the files to PNG-8 or GIFs. You can still have good looking decorative images within few a hundred bytes of data per image file.

Another great way to make weightless images is to create colored areas, shapes, and borders using CSS instead of image files. Replace as many decorative images as possible with proper CSS codes.

Shrink the image files of backgrounds or wallpapers as much as possible. Make them transparent to reduce the file size greatly and also increase the readability of your site contents.

8. Use Image Sitemaps

If there are JavaScript galleries in your site for image pop-ups, you must create image sitemaps so that the images get noticed by Google.

Web crawlers cannot crawl the images that are not specifically called out in source codes of the webpage. You must create a list of their locations in an image sitemap so that crawlers can know about those unidentified images.

9. Add Captions

If you put captions below your product images, it will be of great help when it comes to SEO. The added captions will explain the products to the viewers. At the same time, Google will also know what the images are about. It will be a great benefit for your business and ranking your product images.

10. Manage Images while Using CDNs

Many of us use (CDNs) content delivery networks for hosting images and other files of out sites. Although they help us with bandwidth issues and page load time, they create some problems with backlinks. Backlinks are very important for SEO, but when you are placing your site in a CDN and storing the images there, those backlinks get altered. The links of the images get replaced by the domain of the CDN such as WordPress. So you might think of not using CDNs for hosting your site if you want to rank your images without any limitations.


The above-discussed 10 must know image optimization tips must be followed if you want to be a successful businessman. Your e-commerce site or blogs will be highly benefited if you can rank all your images properly. This will increase the visitors to your sites and encourage you to grow your sites.