SEO Image Optimization: 10 Proven Ways To Boost Yours

There are some very simple changes you can make to your images to increase the chances of them helping your SEO.

Let's take a look at them one by one.

1. Image File Name - SEO Image Naming Conventions

The file name of your photo is directly read by Google and other search engines in order to show them in image search results.

File names are very easy to change, however it is something we often overlook.

And in fact, image file names do affect SEO. Google even state this in their image publishing guidelines:

So that means, instead of uploading your images to your site with random, non-sensical file names, try changing the file name to be something more keyword focused.

Google actually suggests to use very focused, detailed file names such as:

my-detailed-file-name.jpg.

Here is the SEO Image naming convention I would recommend:

Important Note: Just to reiterate - In your file names use dashes not underscores. Matt  Cutts, head of Google spam team even recommends it.

2. Alt Tags and Title Tags

Google also places a high importance on the alt tags and title tags of your images.

These pieces of content help Google understand what your images and surrounding content are about, helping you rank in image search as a result. 

Changing your alt and title tags in WordPress is very simple, as you can see in the example below:

Above is how it looks when you first add an image (the file name is copied into the title area). Now all you need to do is:

• add your alt tag (keeping keywords in mind at least for the first/most important image)
• add your descriptive image title
• add a caption if you want it to appear below the image
• optionally add a description

To edit your tags after uploading an image, simply click the image in your media and click edit.

Remember: The Alt tag is not only used for SEO, but is also shown when an image can't be displayed or used for the visually impaired (it will be spoken to them).

3. Image Captions and SEO

Let's not forget about the captions in our images, because these can also have an impact on our visitors, which as we know in modern SEO, also affects our search rankings.

Why are captions so important?

People have a tendency to scan out content, rather than read it. And when they see images, they instinctively look at the caption. In fact, this might shock you:

So, if you have an image that is not just there for decoration, add a meaningful or even attention-grabbing caption. It will get our readers to pay attention. And maybe even read more of your post.

That will help your SEO because Google are watching how long people are staying on your site.

4. Image SEO Tools & Checkers

There are a few useful tools out there you might want to try that can help you quickly analyse your web pages and see if there are any image seo problems.

They look at things like:

Although most only focus on Alt Text.

Here is a list of some that I tried that are still relevant, and helpful:

5. Image Load Time

If the load time on your site is slower than average, Google will be much less likely to show your site at the top of search results. And visitors are likely to hit the back button if it loads slower than 2-3 seconds.

And perhaps not surprisingly, images are often the number one culprit of slow loading times.

If your site's speed could use some improvement try reducing your file sizes.

You can do this by resizing and compressing the image with an online tool like Pixlr.

You want to make sure the overall size of you image is not much larger than you actually need it to be (ie. the width of your web page or blog post).

For example, there is not much reason you need an image to be over 1,200 pixels in width on most websites. Whereas a standard image from your camera might be over 4000 pixels wide. A huge waste of space and load times!

You can learn a lot more about load time in this post or check out my short but powerful Website Speed Booster course which teaches you how to do this and more.

6. Know Your Image File Types

It is also important to use the correct file type for your images in order to keep the highest quality with the smallest size possible.

JPEG

JPEGS are one of the most popular file types on the internet, mainly because they work well with very complex images such as those taken with a camera.

JPEGs actually lose their quality when they are compressed (lossy compression) but nonetheless can be compressed to quite a small size before humans can detect the loss of quality. As such, they are one of the best formats for most web graphics. 

JPEGs do not however work very well with letters or lines, so are not very well suited to things like graphics or logos. They also do not support transparency. This is where some of the next formats are more useful.

GIF

GIF files are a much lower quality image than a JPEG image and are best for small decorative images and icons. 

In most cases, you will not even consider using a GIF as there is no real reason. But they can have transparent backgrounds, which JPEGs cannot. 

GIF's are best known for being able to support animation effects. This is in fact when they come in most handy. 

PNG

PNG files allow for many more colors in the file than JPEG and GIF files and they do not lose quality when compressed (lossless compression) as JPEG files tend to do. 

The downside, however, is that they tend to be large from the outset. A PNG file at the same quality as a JPEG is often three times as large.

However,  PNGs are great for things like logos and graphics and with the right compression can produce a very small image size.

PNGs also have a specific Alpha channel, which adds transparency to the image, something that is very important for certain image types like logos, where you need to place them on non-white backgrounds.

Advanced Image SEO

There are more advanced options for improving your SEO such as image site maps, schema markups and open graph code. 

7. Image Site Maps