When you search for an image, you may be wondering how these images are ranked. Why some images appear higher than other images? The following are several factors that the search engine takes into account when ranking an image.
1. Use Unique Image
If you want your image to rank on the search result, you should use a unique image for example a photo you snap with your own camera. If you use stock photo, it won't rank on the image search because there are many duplicate versions of the image on the web. However, Matt Cutts from Google did said that the use of stock photo will not have any impact on your search engine ranking. It is the same no matter if you crop the image or create a border around it and then post it into your blog. The search engine is able to detect that you are using the same version of the image.
2. Type of Image Formats
There are three main types of image formats including jpeg, png and GIF. JPEG can be used to represent complex visuals on the website. PNG is suitable for use in screenshots and graphics. GIF is suitable to be used in animations.
3. Size of the Image
The image size is also a factor that Google takes into account when ranking the images. According to a study, image with a great number of pixel has higher chance of getting clicked. This is one of the reason why search engine will rank image with higher pixels in the search result.
4. Distance of the Image to the Text
The distance of the image to the relevant text can also affect its ranking in the image search result. Some of things that affect the distance of the image from the text include number of intervening words, data tags and row tags.
5. Name of the Image File
Often, we don't care about the file name of the image when uploading to the blog. Actually, the file name of the image plays an important role in the ranking of your image on the search result. Instead of naming your image file with numbers or pic.jpg, you should name the file accordingly. When naming an image, you should remove all the adjectives such as the and are. It is best to name the image based on the post title. You can add dash and hyphens in between the words.
6. Image Alt Tag and Title Tag
A lot of importance is also placed on the image's alt tags and title tag. Google recommends webmaster to make the alt tag descriptive. You can name the alt tag the same as the blog post title if the image is the first one to be displayed in your blog post. You can minimally describe the other images that are displayed following the main image in the blog post. If you are using WordPress, you can easily change the alt tag and title tag of the image via the Add Media button. It is optional to add a description. If you add a description, it will appear as a snippet right below the image in the blog post. If you want to edit the image tags, you just have to select the image with your mouse and click edit.
According to SEO experts, there must be at least 200 characters in the image title and alternative text. You can use the same text in the image title and alternative text. To reach up to 200 characters, you can include the image title, description, Pinterest URL and hash tags.
7. Slow Loading Time
Google will rank your site lower in the search result if it has a slow loading time. Everyone knows that the image is one of the culprit for slow load time. Resizing and compressing the image can make the file size smaller so that it takes lesser time to load on the page. You can use image editor such as Photoshop, and GIMP Editor to edit the size and quality of the image. You only have to resize the image up to the image you need. For example, if there is an image slider on your homepage, you just need an image that is 620 pixels so you can use an image is between 620 pixels – 1200 pixels and no need to use image that is too big like more than 5000 pixels wide. You should only compress the image to the point you see visible image quality. Resizing and compressing the image will help you to save hard disk space.