ShortPixel Image Optimizer – Optimize Images, Convert WebP & AVIF for WordPress Plugin Directory

🚀 The Ultimate Image Optimization Plugin for WordPress ⚡ Boost your site’s speed instantly! Optimize images and PDFs with one click, bulk compress to WebP and AVIF, use lazy loading, and resize images.

Increase your website’s SEO ranking, number of visitors, and ultimately your sales by optimising any image or PDF document on your website.

The ShortPixel plugin is a lightweight, user-friendly, install-and-forget solution for image optimization.

It is designed to work with any website type, whether it’s a small blog or a large WooCommerce-powered online store with tens of thousands of products.

Additionally, it’s an excellent choice for agencies, offering unlimited image optimization credits for a flat monthly fee.

🎬 Ready for a Quick DEMO of our Top Image Optimization Tool? Test our plugin here.

Make an instant image compression test of your site or compress some images to test our optimization algorithms.

💡 Why is ShortPixel the best choice for image optimization or PDF compression? 🆕 New! Brand new AI features

AI Image Upscale (2x, 3x, 4x) – Upscale smaller images with high-quality AI upscaling, perfect for retina displays and crisp visuals.

AI Background Removal – Instantly remove background from your images with one click, ideal for creating clean product photos. After the background is removed, your image can have a transparent background or be filled with a single solid color.

AI Image Titles – In addition to ALT text, captions, and descriptions, you can now generate smart image titles using AI for better SEO.

Bulk Remove AI Data – Easily clear all AI-generated image SEO data in one go.

You can now add fixed text before/after AI-generated image SEO data for full consistency across your site.

🆕 New! Freshly added AI Image SEO features

AI-powered image SEO – Automatically generate ALT text, captions, and image descriptions for all your images.

Bulk mode – Mass-generate and update details for all your images.

Preview mode – Test and fine-tune AI results before applying new ALT texts and descriptions in bulk.

Multilingual – Support for 100+ languages.

WooCommerce – Seamless support for WooCommerce product images.

Unlimited credits – AI-generate image titles, captions, and more with our Unlimited plan.

Accessibility – Improve website accessibility by generating all the necessary metadata for each image.

Freshly added features

Smart Backups: Save disk space by backing up only the main image. When restoring, thumbnails are automatically regenerated based on current settings.

Automatic Backup Cleanup: Set rules to automatically delete old backups after a chosen period.

Compress WebP images – ShortPixel now also smartly compresses all your existing WebP images.

Added support for serving CSS, JS and fonts from our global CDN.

Save & Restore option for all settings – ideal for agencies and users managing multiple websites.

Decide whether AI bots can use your images for machine learning (ML) training, or block them entirely.

You can now exclude images from optimization based on their file zie, perfect for skipping very small images or large images that photographers need to keep in their original, full format.

Filter and select images in bulk using date-based criteria, giving you precise control over what gets optimized and when.

🌍 Faster Websites for Global Audiences The ShortPixel plugin now includes a built-in global Content Delivery Network (CDN). This powerful feature ensures that ShortPixel-optimized WebP and AVIF images, as well as your website’s CSS and JavaScript files, are delivered quickly and efficiently to any location worldwide, minimizing delays and improving load times.

By leveraging this built-in solution, you enhance the user experience, reduce server strain, boost SEO performance, and simplify website management — all with minimal effort.

📸 Resize and Compress Images Without Losing Quality

Popular plugin with over 300,000 active installations – according to WordPress

Compress JPG (and its variations: JPEG, JPEG 2000, JPEG XR), PNG, GIF (still or animated) images, and also PDF documents.

Option to automatically convert PNG to JPG if that results in smaller images (ideal for large PNG pictures).

CMYK to RGB conversion.

Progressive JPEG is used whenever it leads to a smaller image.

🌟 Lossy and Lossless image compression Both Lossy and Lossless image compression are available for the most common image types (JPG, PNG, GIF, WebP, and AVIF) plus PDF files.

We also offer Glossy JPEG compression which is a very high-quality lossy optimization algorithm. Especially designed for photographers or for high-quality product pictures.

Optimized images lead to a better user experience, improved PageSpeed Insights or GTmetrix results, higher Google PageRank, and more visitors.

🔄 Convert WebP and AVIF Formats

Option to automatically convert JPEG, PNG, or GIF to WebP and AVIF for better performance and improved Google ranking.

Automatically optimize your existing WebP files with ShortPixel’s SmartCompress algorithm.

Animated GIFs can be automatically converted to much smaller animated WebP or AVIF files.

Option to include next-gen images (WebP and AVIF) in front-end pages with a single click using the tag.

📦 Bulk Image Optimization and Background Image Processing

New! With ‘Background mode,’ images can now be optimized without needing to keep a browser tab open.

Easily add recurring cron jobs for background optimization, ideal for sites where users upload images via the front end.

Bulk-optimize all images in the Media Library or any gallery with a single click.

Full WP-CLI support for background processing, especially useful for large Media Libraries.

🔥 Performance and Automatic Image Optimization ShortPixel uses minimal resources and works well with any shared, cloud, VPS, or dedicated web hosting. It can optimize any image on your website, including those not listed in the Media Library, such as images in galleries or those added directly via FTP.

All optimization is performed using ShortPixel’s Image Optimization Cloud, so your hosting resources remain unaffected.

New! Automatic scan of Custom media folders for new images using cron jobs.

Skip already optimized images to avoid redundant processing.

🎨 Compatibility with Popular Themes, Page Builders, and Media Library Plugins

Works great for eCommerce websites using WooCommerce and other plugins.

Compatible with NextGEN Gallery, Modula, Foo Gallery, and other galleries or sliders.

Fully compatible with WP Retina 2x, including automatic compression of retina images.

Works seamlessly with WordPress multisite installs (sub-folders or sub-domains) using a single API key.

Compatible with WPML and WPML Media plugins.

Fully compatible with WP Offload Media plugin.

Supports both HTTPS and HTTP websites.

Compatible with virtually all hosting providers.

Integrates with Gravity Forms’ post_image field type to optimize images upon upload.

Works with watermarking plugins.

Integrates directly with Cloudflare via a Cloudflare Token, automatically synchronizing updates with Cloudflare cache.

New! HEIC file support

With ShortPixel, you can now add images in Apple’s HEIC format directly from your iPhone. They will be automatically converted to JPG and optimized according to your settings. Easy!

Read more.

🔧 Advanced Image Optimization Features

NEW Smart Cropping: Generate subject-centered thumbnails using AI, ideal for eCommerce websites.

Optimize thumbnails and featured images, with options to exclude individual thumbnails from optimization.

Advanced exclusion options (exclude images based on filename, path, size, or complex regex).

Ability to optimize any image, including those in NextGEN Gallery and other image galleries or sliders.

Option to scale images down, with two automatic resizing options for large images (applicable to featured images).

Option to deactivate auto-optimization of images on upload.

Keep or remove EXIF data from images, which is especially useful for photographers or for enhanced privacy.

Easily test lossy, glossy, or lossless versions of images with a single click in the Media Library.

100MB filesize limit

🛡️ Backup and Safety

Safe to test and use: original images are backed up locally and can be restored with a single click (either individually or in bulk).

No credits are used for images optimized by less than 5%

Save & Restore option for all settings – ideal for agencies and users managing multiple websites.

Decide whether AI bots can use your images for machine learning (ML) training, or block them entirely

📊 Reporting, Analytics, Compliance and Customer Support

30-day optimization report with detailed image statistics and overall site performance improvements.

24/7 stellar support.

We are fully GDPR compliant.

🚀 New Plan: ShortPixel Unlimited

This is the ideal monthly plan for web agencies or website owners with multiple sites and frequent image uploads.

It allows you to optimize an unlimited number of images with ShortPixel Image Optimizer or use ShortPixel Adaptive Images without worrying about CDN traffic limits.

Read more details on our dedicated page.

free optimization credits for non-profits, contact us for details

💸 How much does it cost?

ShortPixel comes with 100 free credits per month, and additional unlimited monthly credits can be purchased for $9.99.

One-time credit packages that never expire are available starting at $19.99.

Check out our prices.

🌟 Testimonials:

★★★★★ A Super Plugin works very well 62% reduction overall. robertvarns

★★★★★ The secret sauce for a WordPress website. mark1mark

★★★★★ A must have plugin, great support! ElColo13

★★★★★ Excellent Plugin! Even Better Customer Service! scaliendo

★★★★★ Great image compression, solid plugin, equally great support. matters1959

more testimonials

Help us spread the word by recommending ShortPixel to your friends and collect 100 lifetime monthly additional image credits for each referred active user. Make money by promoting a great plugin with our 30% commission affiliate program.

🛠️ Other plugins by ShortPixel

FastPixel Caching – WP Optimization made easy

ShortPixel Adaptive Images – On-the-fly image optimization & CDN delivery

Enable Media Replace – Easily replace images or files in Media Library

reGenerate Thumbnails Advanced – Easily regenerate thumbnails

Resize Image After Upload – Automatically resize each uploaded image

WP SVG Images – Secure upload of SVG files to Media Library

ShortPixel Critical CSS – Automatically generate above-the-fold CSS for fatster loading times and better SEO scores

📩 Get in touch!

Email https://shortpixel.com/contact

Twitter https://twitter.com/shortpixel

Facebook https://www.facebook.com/ShortPixel

LinkedIn https://www.linkedin.com/company/shortpixel

Actions and Filters for Developers The ShortPixel Image Optimizer plugin calls the following actions and filters:

do_action( 'shortpixel_image_optimised', $post_id );

upon successful optimization;

do_action("shortpixel_before_restore_image", $post_id);

before restoring an image from backup;

do_action("shortpixel_after_restore_image", $post_id);

after succesful restore;

apply_filters('shortpixel_image_urls', $URLs, $post_id);

filters the URLs that will be sent to optimisation, $URLs is a plain array;

do_action('shortpixel/image/after_restore', $this, $this->id, $cleanRestore);

This action can be used to cleanup the meta data from the database, regenerate thumbnails after restoring the main file, writing the updated meta data, etc.

apply_filters('shortpixel/settings/image_sizes', $sizes);

filters the array ($sizes) of image sizes that can be excluded from processing (displayed in the plugin Advanced settings);

apply_filters('shortpixel/image/imageparamlist', $result, $this->id, $this);

filters the list of parameters sent to the API so that resizing can be performed more granularly;

apply_filters('shortpixel/api/request', $requestParameters, $item_id);

filters the parameters sent to the optimization API (through $requestParameters), described in detail here: ShortPixel Reducer API; $item_id contains the ID of the Media Library item, or the ID of the Custom Media item (when used). In short, this filter can be used to alter any parameters sent to the API, depending on the needs. For example, you can set different resize parameters for different post types, different compression levels, remove EXIF or not, covert WebP/AVIF, and basically any other parameter that is sent to the API for a specific image (together with all its thumbnails).

This filter enables the background ShortPixel processing in additional pages (see here the original list). Here’s an example of this filter that enables the processing on the Comments screen (to be placed in your functions.php file):

add_filter('shortpixel/init/optimize_on_screens', function ($screens) { $screens[] = 'edit-comments'; return $screens; });

The edit-comments is the ID of the screen where you want to enable the processing.

If you want to add multiple pages, here’s what the snippet looks like:

add_filter('shortpixel/init/optimize_on_screens', function ($screens) { $screens = array('edit-comments', 'plugins', 'another-custom-post-type-page'); return $screens; });

add_filter('shortpixel/image/filecheck', function () { return true; });

This filter forces a file check for WebP/AVIF in case they were manually removed from disk.

If you want to disable the automatic cache flush that is triggered after image optimization, you can use this filter:

add_filter( 'shortpixel/external/flush_cache', function() { return false; } );

In order to define custom thumbnails to be picked up by the optimization you have two options, both comma separated defines:

define('SHORTPIXEL_CUSTOM_THUMB_SUFFIXES', '_tl,_tr');

will handle custom thumbnails like image-100x100_tl.jpg;

define('SHORTPIXEL_CUSTOM_THUMB_INFIXES', '-uae');

will handle custom thumbnails like image-uae-100×100.jpg;

define('SHORTPIXEL_USE_DOUBLE_WEBP_EXTENSION', true); define('SHORTPIXEL_USE_DOUBLE_AVIF_EXTENSION', true);

will tell the plugin to create double extensions for the WebP/AVIF image counterparts, for example, image.jpg.webp/image.jpg.avif for image.jpg;

Enable the “Trusted mode” in case the file system has limitations and is very slow in responding to direct file operations by adding this constant:

define('SHORTPIXEL_TRUSTED_MODE', true);

This will simply skip file check operations and if the Media Library loads very slowly or freezes, you might want to try adding the constant above to your wp-config.php file.

Disable the feedback survey when the plugin is deactivated:

define('SHORTPIXEL_SKIP_FEEDBACK', true);