15 Must-Have Image Optimization Plugins for WordPress

Every website owner is concerned about the load time of their websites. It is an important factor which contributes in overall website performance. Search engines, notably Google introduced speed in their ranking algorithm a few years ago. Yet, the average site runs above 10 seconds to the user. Big guns like Facebook, Twitter and Google deliver their site in under 2 seconds to the user. Yours should shoot for the same performance.

WordPress comes with a wide range of plugins which can help you enable different functions into your site. This includes search engine optimization, profanity filtering, anti-spam protection, chat and comment management. Here we have 15 Must-Have Image Optimization Plugins for WordPress which can help you optimize the images on your site.

Smush.it

Smush.it reduce image file sizes and improve performance using the Smush.it API within WordPress. This plugin strip meta data from JPEGs, optimize JPEG compression, convert certain GIFs to indexed PNGs and strip the un-used colours from indexed images.
Every image you add to a page or post will be automatically run through Smush.it behind the scenes. You don’t have to do anything different.

PB Responsive Images

The PB Responsive Images plugin automatically reformats all images in the post content into a format similar to the picture tag proposed by the Responsive Images Community Group on w3.org.

The default configuration provides the necessary image sizes for the Twenty Eleven theme for reference; you'll have to customize the configuration to fit your theme best. Eace image is reformatted based on standard CSS media queries and SLIR image query pairs, giving a huge amount of flexibility in the variety of query combinations.

EWWW Image Optimizer

The EWWW Image Optimizer is a WordPress plugin that will automatically and losslessly optimize your images as you upload them to your blog. It can also optimize the images that you have already uploaded in the past. It is also possible to convert your images automatically to the file format that will produce the smallest image size.

Lazy Load

This is a really cool plugin. It uses jQuery.sonar to load only necessary images. If you have a large image halfway down a blog post, it will only load when the user sees the spot where it should be. Everything is is loaded beforehand, resulting in a smoother browsing experience.

Watermark Reloaded

This plugin allows you to watermark your uploaded images. You can create watermark with different fonts, colors and apply those watermarks to different image sizes (thumbnail, medium, large, fullsize). You can also position the watermark anywhere on the image within Watermark RELOADED settings. Watermarking settings are simple to use and provide you with instant preview of how your watermark will look like on the uploaded image.

Hammy

Hammy takes your regular content images (only within posts and pages, not custom post types) and regenerates a number of smaller sized images. When a person visits your website, it then automatically provides them with the most appropriate image (or the smallest one possible). This makes for a better experience, especially on mobile. This uses the new WP 3.5 image code.

SEO Friendly Images

SEO Friendly Images is a WordPress SEO plugin which automatically updates all images with proper ALT and TITLE attributes for SEO purposes. If your images do not have ALT and TITLE already set, SEO Friendly Images will add them according to the options you set. Additionally this makes the post W3C/xHTML valid as well.

Bulk Resize Media

This is a plugin that utomatically resizes large image uploads, keeping the maximum size and removing the original huge image. It feature to selectively resize all existing attachments and optionally converts BMP files to JPG. You can configure the maximum width and height, as well as the jpeg quality.

Media File Renamer

By updating the name of the image / media, this plugin will rename physically the filename nicely, update all the references to that media in the associated post if there is any (img, src, url...). Using File Renamer (in Tools), you can bulk-rename all your files all at once, or only the flagged files, but it's recommended to do the renaming through the Media Library directly.

Image Pro

Image Pro WordPress plugin is a totally different approach to Image and Media management in WordPress. Now you can easily add, edit, resize, remove images. It fully replaces WordPress image upload system with a completely new one, which is faster and more fun to use. Images are responsive by default. They will resize nicely on lower resolution devices

Imsanity

Imsanity automatically resizes huge image uploads down to a size that is more reasonable for display in browser, yet still more than large enough for typical website use. The plugin is configurable with a max width, height and quality. When a contributor uploads an image that is larger than the configured size, Imsanity will automatically scale it down to the configured size and replace the original image.
Imsanity also provides a bulk-resize feature to selectively resize previously uploaded images to free up disk space.

NextGEN Gallery

NextGEN Gallery is one of the most popular WordPress plugins of all time, with over 7.5 million downloads. It provides a powerful engine for uploading and managing galleries of images, with the ability to batch upload, import meta data, add/delete/rearrange/sort images, edit thumbnails, group galleries into albums, and more. It also provides two front-end display styles (slideshows and thumbnail galleries), both of which come with a wide array of options for controlling size, style, timing, transitions, controls, lightbox effects, and more.

Google XML Sitemap for Images

XML Sitemaps are a way to tell Google, Bing and other search engines about web pages, images and video content on your site that they may otherwise not discover.
The Image Sitemap plugin will generate a sitemap for your WordPress blog with all the image URLs that are attached to your blog posts and WordPress pages.

Klix Image DimSum

This plugin resizes all blog images (home, post and pages) to their tagged width and height, and changes the compression for a perfect balance between quality and speed as seen fit by you, the site owner. It makes elephants into bite-sized dimsum whenever possible.

The CW Image Optimizer

The CW Image Optimizer is a WordPress plugin that will automatically and losslessly optimize your images as you upload them to your blog. It also optimize the images that you have already uploaded in the past.
The CW Image Optimizer plugin is based on the WP Smush.it plugin. Unlike the WP Smush.it plugin, your files won’t be uploaded to a third party when using CW Image Optimizer.