I have a confession to make. I’m not perfect and I learn everyday. Up until recently I was not making such a big deal about image optimization, if the image file size looked ok to me I would go with it. If I thought it was too heavy then I’ll try to reduce the file size somehow so that it would not slow down the site. Sure I was saving all my images as ‘save for the web’ optimization, but that was it.

That was until last week when Olivier, my other half and business partner in the WP Help Club first talked to me about… Image SEO and how we can improve site performance and google rankings by carefully optimizing images used on the website.

Here is the thing: if you have a website, chances are you are using images for your website. Header, images in your posts, images in your sidebar. We know how powerful images can be. What you might not know is that images can really slow down your website and hurt your google rankings if you don’t follow simple rules.

1) file format:

Whenever you can choose jpg over png (3x bigger). If you need a transparent background, jpg won’t cut it, but otherwise, stick with jpg.

2) Choice of file name

if you are using an image for a blog post you are trying to rank for, use the keyword in the file name, that will let google know what your image is about and definitely help in your rankings. header-123238720.jpg tells nothing to google, but image-optimization.jpg is much more powerful.

3) Size does matter 🙂

Don’t load an image that is really big and then use WordPress to resize it with the width and height, the image still gets loaded big then resized by the browser which slows down your site.
Resize the image first then upload it to WordPress. Takes a little bit more time I know, but well worth the effort.

4) Use Optimizer tools

Run your images through an optimization tool before you upload them to your site.
There are several tools out there that will optimize your images for the web and drastically reduce the file size. Our favorite so far is
tinypng.org
this is the one where we got the best results.
Another one I like is
http://tools.dynamicdrive.com/imageoptimizer/
because it gives you options and you can decide what definition you’d like and compare images before you choose which one you’re going to use.
here is a little test I ran on an image. The first one at the top is the original image, the ones below are options that I have and I can choose to download which one I want based on the size file/quality of the image.
Just right click and save the images on your computer.

tinypng

As an example this image just above was originaly 360Ko, just saving it as a jpg brought it down to 152Ko, that’s a over-50% gain.

5) Add Alt Text to your images

Something that many people never do is to add the alt text to your images so that google know what the image is about. it can be the file name or a keyword if you’re trying to rank for a particular keyword. google can’t see images, it only sees text so you need to tell him what this image is about.
image-alt-text

Now I’d like to hear from you: are you already doing some image SEO or is that completely new to you? Would you be interested in finding out more about it? let me know in the comments below!