WP-Optimize preload key request feature details

The latest updates for WP-Optimize 3.1.7 have now been released – including the preload key request feature. We have taken a lot of time and effort to launch these new improvements and hope that they further help improve users’ experience of WP-Optimize. 

When aiming to improve the speed of your WordPress site using WP-Optimize, one of the new features we have released with this update is the ability to preload key requests. Preload key works by using an audit to identify which resources to preload on your WordPress site. The browser will then preload resources so they are available immediately when needed, preventing eventual waiting time later on, making your site load faster. Google’s pagespeed insights will often suggest preloading the requests to font files and other assets as a speed improvement:

With the latest WP-Optimize Premium release, you now have the ability to manually add any resource you want to be preloaded:

As can be seen in the Google PageSpeed insight test, preloading key requests can result in massive time savings when visitors are loading your site.


In order to get the URL to add to WP-Optimize, just right click on the resource and copy the URL:

Next, past the URL in the ‘New Asset’ box of the ‘Preload key requests / assets’ section of WP-Optimize and press ‘Add’. 

The URL you added you will be added to your preload key requests.

The updates to WP-Optimize 3.1.7 also includes the following:

WP-Optimize: 3.1.7

  • FEATURE: Premium – Preload key requests (Preload fonts and other assets)
  • FIX: Detecting Brotli compression issue
  • FIX: Cache – PHP Warning in URLs to exclude from caching
  • FIX: Premium – Unused images – Unused Images Tool not recognising Greek characters
  • FIX: Button for disabling Gzip doesn’t showing
  • TWEAK: Database optimization – Prevent fatal error due to files missing
  • TWEAK: Skip minify when SCRIPT_DEBUG is set to true
  • TWEAK: Fixed Font-awesome settings
  • TWEAK: Add support for different spellings of “Font-awesome”
  • TWEAK: Update the feature comparison table
  • TWEAK: Added the option to not show the warning before deleting a table
  • TWEAK: Wipe all options upon plugin de-installation
  • TWEAK: Premium – Lazy-load – Lazy load support for background images
  • TWEAK: Minify – Add file size in the minify cache summary
  • TWEAK: Detect conflicting plugins for GZIP issue
  • TWEAK: Database optimization – Include all tables if database prefix is not set on WP install
  • TWEAK: Premium – Unused images – added “X of X images loaded” for unused trash images
  • TWEAK: Don’t allow to remove actionscheduler_ tables
  • TWEAK: Premium – Unused images – Show a progression screen when doing any action with unused images
  • TWEAK: Cache – Enable cache for the old default permalink structure domain.com/index.php/a-post-name by creating a folder without the extension
  • TWEAK: Show previous action as message on Trackbacks or Comments enable or disable.
  • TWEAK: Prevent deprecation notice on PHP 8.0
  • TWEAK: Update notices


How to optimize WordPress images with WP-Optimize

Post updated: 7th February 2023

Websites can accumulate hundreds, if not thousands of images over time. Images in their original uncompressed format can slow your website down, impacting user experience, bounce rate, and SEO performance. 

This article outlines how to improve the speed of your site by optimizing images using WP-Optimize.

WP-Optimize ‘Free’ or Premium?

Image compression is included in both packages but when it comes to page load speed and SEO, every little bit helps.

Premium features includes ‘Lazy load’, which loads only parts of a web page that are visible to the user, allowing a page to load much faster. Additional benefits of Premium include multi-site support, scheduling so you can ‘set and forget’ and premium support. You can find out about the benefits of WP-Optimize Premium here.

How to optimize your images

Step 1

Once you have installed the WP-Optimize plugin, go to WP-Optimize > Images in your WordPress dashboard. Now you can decide what level of compression you want for your images. There are three options:

  • Prioritize maximum compression 
  • Prioritize retention of detail 
  • Custom

You’ll save the most space by selecting “Prioritize maximum compression“. This compresses your images, making them smaller and quicker to load, and as a result, your WordPress site will load faster. However, if you run a wedding photography website, for example, you may not want to compress your images fully, as there can be a slight drop in image quality the more an image is compressed. While the loss in quality is hardly noticeable for most people and is not a consideration for most websites, if high-end quality images are essential to you, then you should select “Prioritize retention of detail“. This option will still reduce the image file size (though not as much as ‘maximum compression’) but will maintain the high quality of the original image. You can also select “custom“, if you would like to format your images to a level that is not quite maximum compression or best image quality. 

Step 2

image optimization screenshot

Below the settings options, you will see all the Uncompressed images uploaded to your website. Here, you can manually select individual images you wish to compress or press the “Select All” button if you want to compress all the images to the same level. As previously mentioned, if you have high-quality images that you do not wish to fully compress alongside other images that may not be as important, you can individually select them and run a ‘maximum retention of detail’ compression. You can then run the ‘maximum compression’ option on the remaining images.

Step 3

WP-Optimize also gives you ‘advanced options‘ when compressing your images. Here you can choose options such as: 

  • Preserve EXIF data – Handy for professional photographers that may require the EXIF data at a future date.
  • Backup original images – Don’t worry if you make a mistake or want to revert to the original image. WP-Optimize gives you the option to retain a backup.
  • Automatically delete image backups – Once you have compressed your images, you can set a date for when you want your backup images deleted. This helps prevent your site from storing large original files that are no longer needed. 
  • Delete all backup images now – If you are happy with the results and want to delete all your backed-up images, press this button, and WP-Optimize will do the rest. 
  • Mark all images as uncompressed – Use this option if you want to compress your images again or make further changes.
  • Restore all compressed images – If you decide that you no longer want your images compressed or have made a mistake and still have the original in your media library, you can restore all of your compressed images to their original state.

image optimization screenshot

Step 4

Once you have set up and decided what kind of image compression you are happy with, you can tick the “Automatically compress newly-added images” button so that you do not have to go through the process every time you upload a new image. Once you activate this option, every new image you upload will be compressed according to your chosen settings (compression or detail). 

If you would like to read more information on the benefits of compression versus detail, check out the following blog that goes into more detail and explains the benefits of both: Lossy vs Lossless image compression – A guide to the trade-off between image size and quality.

We have also put together a video of how to optimize your images:


A version of this article was initially posted on the UpdraftPlus blog as “How to use WP-Optimize image compression.”