Images are crucial for SEO; if you do a bit of research yourself, you will find that Google ranks sites with at least one image, higher than sites with no images at all.
Images make your content more visually appealing, and you can explain your concept more easily. Users are also more likely to share content that has quality images; Google search engines can also better understand what you’re conveying by matching it with the images on your site. All these factors help to rank your site higher in Google, and you can get more qualified traffic to your site.
Here’s a checklist to follow to ensure that your images are optimized for search engine bots:
Did you Optimize the Image Filename?
An image filename must be informative and describe the image precisely, and in the least number of words possible.
E.g: instead of IMG123.jpg, redjumper-neck-closeup.jpg (clearly describes the image, no confusion)
Did you optimize the file size of the Image?
As a rule, the lesser the bytes the image file takes, the better. Large files load slowly and may negatively impact user experience.
Use image optimization tools like Pixelmator or imageoptim to adjust file size without compromising on quality.
Are your images responsive?
WordPress now offers native support for responsive images; meaning, when you upload an image into WordPress, it automatically creates many images in different sizes; it will serve the image size to a user depending on their device.
You can also implement responsive images using CSS. Responsive images results in smaller file sizes and lower bandwidth use.
Did you optimize the Image Alt text?
Search engine bots need ALT text to understand what your image is; it is also used to describe the contents to visually impaired people. Remember this when writing ALT text:
Don’t use dashes; describe in a few words what the image is
Use keywords relevant to your page content
ALT text should be brief and crisp (e.g: <img src = “jumper.jpg” alt = “jumper”)
Did you optimize the Image Caption and title?
It’s good practice to provide a title and a caption to your image as these help the search engine crawlers to understand the subject matter of your image.
Did you Optimize the Image Placement?
Placement of the image can be done anywhere; however, having the image right at the top with relevant ALT text, caption and title conveys to the search engine bots that this is important.
Did you add Schema?
Structured data helps search engines to understand a page content much better; for images, image schema can be implemented by including relevant structured data on the page.
This will enable Google to show your images in results, driving more traffic to your site.