Visitors patience for loading times are decreasing dramatically, with 25 percent of users leaving a webpage if it takes longer than 4 seconds to load. Optimizing your images boosts your sites SEO and makes your WordPress site load faster. A faster site helps your rankings climb in the Google search algorithm and keeps your audience interested, converting your web traffic to sales. When undertaking the process it is important to consider different WordPress optimization methods, each with different benefits to assist your image optimization.

Benefits of Optimisation

Before we begin it is important to review the benefits of image optimisation for your sites performance. These benefits include:

  • Faster site speed
  • Responsive web design
  • Search engine rankings improvement
  • Audience retention and conversion. If you are not convinced, supermarket giant Wal-Mart reported a 2% increase in conversions for every 1 second of site speed improvement.
  • Less storage required on your servers, saving you money

Image Formats

In order to successfully complete image optimisation for your WordPress site it is important to have a knowledge about image formats and which format will be the best for image optimization in each specific case. The two most common image formats on the internet are PNG and JPEG files.

In general, the PNG format is best for images with limited colour (such as logos), whilst the JPEG format is the best format for photos and images with many colours. Choosing the incorrect format to save your image, can make you file size over 45% larger than is necessary.

Resize Images

Before uploading an image it is vital to understand the width and container size of your WordPress site. Resizing the image before uploading to correspond with the maximum width further reduces the image file size. If you upload an image that is larger than the maximum width of the page, WordPress will automatically reduce the measurements to fit the page. This however does not reduce the image size, which is key to image optimization and site performance.


WordPress plugins are able to compress images in a way that reduces the file size but not the visual quality of the image. Image compression plugins work by stripping unnecessary metadata from JPEG files, converts GIF’S to smaller PNG files and strips unused colours from indexed images.

Some plugins also have the ability to convert your images to the file format that produces the smallest image size without sacrificing the overall visual quality of the image. These plugins can also be useful when optimizing your images for SEO.

WordPress Plugins for image compression

Popular WordPress plugins for image compression include:

  • WP Smush
  • ShortPixel
  • Imagify
  • EWWW Image Optimizer

Online Tools for Image Compression

Other popular tools for image compression include:

  • Optimizilla
  • Tiny PNG
  • Compressor
  • ImageOptim
  • ImageSmaller

Manual Image Optimization

Manual  optimization is best for users who want to retain control over your images. Images can be edited in programs including Adobe Photoshop, saved “for the web” and then reduced in file size using programs such as JPEGmini or RIOT.
For image optimisation to be successful, there are just 3 simple steps:

1. Resize images before uploading.

2. Select the correct image format.

3. Compress images with WordPress plugins or online tools.

A well-designed and responsive website is vital in order to attract your ideal customer and increase conversion rates. A website that is too cluttered for users to navigate, slow to respond and unresponsive on mobile phones is unlikely to engage and inspire your audience. Image optimization is a key step to ensuring your WordPress sites performance, providing your website with the speed and responsiveness that will convert your web traffic into sales.