Kraken.io Image Optimizer – Compress, Convert to WebP & AVIF, Resize & Bulk Optimize vs Robin Image Optimizer – Unlimited Image Optimization, WebP & AVIF

⚡ Compress, resize and convert your WordPress images to WebP, AVIF and more — automatically. Faster pages, smaller files, same quality. Slow pages cost you visitors, search rankings and sales — and over-sized images are almost always the culprit. Kraken.io Image Optimizer fixes that on autopilot: it compresses, resizes and converts every image you upload — and every thumbnail WordPress generates — so your whole site loads lighter and faster, without you lifting a finger. Every upload is sent to Kraken.io, one of the most advanced image-optimization APIs on the web, optimized in the cloud, and pulled straight back into your Media Library. No binaries, no command line, no server tweaks — install it, add your API key, and stop worrying about heavy images. At its heart is Kraken.io’s intelligent lossy engine: for every single image it finds the exact point where the file is as small as possible while staying visually indistinguishable from the original. Expect to cut 60% or more off your image weight — exactly the win Google PageSpeed and Core Web Vitals reward. From a personal blog to a busy WooCommerce store with tens of thousands of products, it’s an install-and-forget solution that just works. ✨ Why Kraken.io Intelligent lossy & lossless — pick maximum savings with no visible quality loss, or pixel-perfect lossless. Per-image JPEG quality and chroma subsampling control for power users. Convert between formats — turn uploads into WebP, AVIF, JPEG, PNG or GIF. Reach for next-gen WebP or AVIF for the biggest savings (and to clear Google’s “Serve images in next-gen formats” audit), or switch between the classics — whatever fits your site. Optimizes everything WordPress serves — the full-size image and every thumbnail size (thumbnail, medium, large, …) that actually reaches your visitors through responsive srcset. PDFs too, not just images — PDF files in your Media Library are compressed through the same Kraken.io engine, so documents download and embed faster. Smart resizing — cap oversized uploads to a maximum width/height; resized images are enhanced to stay sharp and avoid haloing. Bulk “Krak ’em all” — optimize your entire existing library from a dedicated Bulk Optimize screen or the Media Library bulk action, with live progress. A control panel that tells you everything — a Kraken.io summary panel on the Media Library, Add Media and Plugins screens (plus a Dashboard widget) shows your connection status, plan, quota usage, active settings and supported formats at a glance. Per-image savings & error badges — see exactly how much each image saved, right in the Media grid and list. Plays nice with your stack — works with multisite, page builders, CDNs and local/dev sites. Detects other optimizer plugins and offers one-click deactivation so they don’t fight over your images. 🖼️ Supported formats JPEG, PNG, animated GIF, WebP, AVIF, HEIC/HEIF and PDF. (For security, raw SVG upload is intentionally not enabled — see the FAQ.) ⚡ Built for Core Web Vitals Heavy images are the number-one cause of slow pages. By compressing every size, converting to WebP/AVIF and right-sizing oversized uploads, Kraken.io directly targets the audits that move your score: Properly size images, Efficiently encode images, Serve images in next-gen formats and Largest Contentful Paint. 🎛️ Your images, your control Choose intelligent lossy or lossless, globally. Convert uploads to WebP/AVIF/JPEG/PNG/GIF on the fly — synced live between the panel and settings. Preserve selected EXIF tags (Date, Copyright, Geotag, Orientation, Profile) or strip them for the smallest files. Auto-orient photos from phones and cameras by their EXIF orientation. Decide who can optimize — all logged-in users, authors and up, or administrators only. Pick exactly which image sizes to optimize (the large 1536×1536 and 2048×2048 retina sizes are off by default to save quota — turn them on if your theme serves them). Optimize on upload automatically, or defer and bulk-optimize later. 🔒 Private & secure by design Your API credentials are stored write-only and masked — they are never pre-filled into the page or exposed in your site’s source, so other users on the dashboard can’t read them. Every action is protected by nonces and capability checks, uploads are content-verified, and all optimization happens server-to-server with Kraken.io. No secrets ever reach the browser. 🚀 Get started for free Create a free Kraken.io account — no credit card required — and get testing quota to try the plugin and the rest of the Kraken.io toolset: A fully-featured optimization API with official libraries for PHP, Node.js, Python, Ruby, Java, Go and .NET Web Interface (free) and Web Interface PRO with resizing and sync-to-Dropbox URL Paster and Page Cruncher to optimize images in bulk from anywhere on the web Optimization history and stats, and Kraken.io Cloud Storage You can use a single API key across as many sites as you like — there is no per-site license. ★★★★★ Excellent option for image optimization “The real power of Kraken is their ‘intelligent lossy’ optimization. I use it on all my sites and have never once needed to roll back an image because of too much quality degradation. It is a perfect solution as is.” — collin ★★★★★ Quality results, quality service “The plugin works really well and effortlessly, and the support is prompt, thoughtful, and thorough. I’m hooked.” — illustrata ★★★★★ Optimize according to Google PageSpeed “Kraken was instrumental in optimizing images to comply with Google’s PageSpeed analyzing tool. Our travel blog now sports Google’s ‘mobile friendly’ tag for mobile searches.” — Walter Schaerer ★★★★★ Perfect solution to speed up site! “I love this plugin! All my questions are quickly responded to and I see a huge saving in image size without losing quality. Highly recommend!” — ezone69 Connect with Kraken.io Website: https://kraken.io Plans & pricing: https://kraken.io/pricing Twitter / X · Facebook · GitHub

🚀 Make Your Website Faster by Reducing Image Weight Robin Image Optimizer is a WordPress image optimization plugin that can reduce image file size by up to 80% without visible quality loss. It helps speed up your site by compressing images, converting them to modern formats, and optimizing both new and existing images automatically. Robin Image Optimizer is a smart and advanced free image optimization plugin for WordPress, built with no limits on the number of images, no API keys, and no external CDN dependency. It works locally inside WordPress and supports automatic image optimization, bulk image optimization, and WebP conversion. Robin is built for site owners who want free image optimization, unlimited WebP conversion, and a simple, local solution that works directly inside WordPress. At a Glance 📌 Unlimited image optimization (no limits) 📌 Automatic optimization on image upload 📌 Bulk optimization for existing media 📌 WebP conversion (JPG, PNG, GIF) 📌 Runs locally inside WordPress 📌 No API keys, no external CDN Quick Links 📘 Documentation – Complete setup and configuration guide 💬 Support Forum – Community help and expert support ⭐ Go Pro – Unlock advanced features and priority support What Robin Does Robin improves WordPress performance by optimizing images throughout your entire workflow. Images are optimized automatically when they’re uploaded, and existing images in your media library can be optimized in bulk. This reduces manual work and keeps your site fast as it grows. By compressing images and converting them to modern formats like WebP, Robin helps reduce overall page size. This results in faster load times, better performance metrics, and a smoother user experience, especially on mobile devices and image-heavy pages. With Robin, you can: Automatically optimize images on upload Bulk optimize existing images in the media library Convert images to modern formats like WebP and AVIF in PRO Reduce image weight and overall page size Improve loading speed and PageSpeed audits Run everything locally without API keys or CDN dependencies This makes Robin a reliable choice for bloggers, content websites, and performance-focused WordPress sites. Why Image Optimization Matters ⚡ The lighter the image, the faster your page loads. Images are often the most significant contributor to page size on WordPress websites. As mobile usage continues to grow, image optimization has become essential for delivering fast, responsive experiences. Unoptimized images can lead to: Slower page loads Higher bounce rates Poor ad and conversion performance Lower engagement on mobile devices Image optimization reduces image file size while preserving visual quality, helping pages load faster without sacrificing quality. How Robin Optimizes Images Robin analyzes each image and applies compression based on the selected optimization mode. Optimization happens automatically and safely, without blocking the WordPress admin interface or requiring manual intervention. ⚙️ Automatic Image Optimization Images are optimized automatically as soon as they are uploaded to WordPress. No manual steps are required, and the optimization process runs quietly in the background. This ensures that all new images added to your site are optimized by default, without interrupting your workflow. 📦 Bulk Image Optimization Robin supports manual bulk optimization for images that already exist in the media library. With a single action, you can start optimizing previously uploaded images. The optimization process runs in batches, making it suitable for large media libraries with thousands of images. This is especially useful for existing WordPress sites that want to reduce page size and improve performance without re-uploading content. 🎚️ Compression Modes Robin provides multiple compression modes so you can choose how aggressively images are optimized. Lossless compression: Reduces image file size without any visible or measurable quality loss. Ideal for logos, illustrations, and high-fidelity images. Lossy compression: Applies stronger compression while keeping quality changes minimal and usually unnoticeable. A great default for most WordPress sites. High compression: Uses more aggressive optimization techniques to achieve maximum file size reduction. Best for performance-focused and image-heavy pages. PageSpeed compression (Pro): Applies optimization settings tuned specifically for improving PageSpeed and performance audits. Custom compression: Allows you to define your own quality level for full control over optimization behavior. 🖼️ Modern Image Formats: WebP & AVIF Robin converts supported image formats such as JPG, PNG, and GIF into WebP, a modern image format that produces smaller files while maintaining visual quality. WebP images are generated automatically when images are uploaded or optimized in bulk. Optimized WebP images are served automatically to browsers that support them. When a browser does not support WebP, Robin safely falls back to the original image format to ensure full compatibility across devices. WebP conversion is available in the free version of Robin with no limits on the number of images. Images are converted automatically and served in the best format supported by each browser. Robin free supports: JPG to WebP conversion PNG to WebP conversion GIF to WebP conversion Other common image formats used in WordPress are also supported, with automatic fallback to ensure compatibility across all browsers and devices. 🏆 Robin Pro adds support for AVIF, a next-generation image format that can deliver even smaller file sizes than WebP in many cases. Safe fallbacks are applied automatically. 💾 Image Backup and Restore Before optimizing any image, Robin stores a backup of the original file. You can restore original images at any time or re-optimize them using different compression settings. This makes it safe to experiment with optimization modes without the risk of permanent changes. 🧾 Strip EXIF data Robin allows you to choose whether EXIF metadata should be removed or preserved during image optimization. Removing EXIF metadata helps reduce image file size and improves privacy. Keeping EXIF metadata is useful for photography portfolios or workflows that rely on image data. 🔄 Background Image Optimization (PRO) Robin supports background image optimization, allowing images to be processed gradually over time without blocking the WordPress admin interface. Background optimization uses scheduled processing to continuously optimize images, preventing timeouts and performance issues when working with large image libraries or frequent uploads. 📁 Custom Folder Optimization (PRO) Robin can optimize images stored outside the WordPress Media Library, including images located in custom folders such as theme directories and plugin assets. This is useful for: Custom WordPress themes Plugins with bundled image assets Performance-focused sites using custom directories Advanced or custom-built WordPress setups WP CLI commands (PRO) Commands wp robin optimize wp robin stop wp robin status Available scopes media-library custom-folders nextgen Use Cases Robin Image Optimizer fits naturally into a wide range of WordPress workflows, from small blogs to performance-focused websites. 📝 Blogs & Content Websites Perfect for bloggers and content creators who upload images regularly and want automatic image optimization without manual work. Images are optimized on upload, keeping pages fast as content grows. 🖼️ Image-Heavy Pages & Media-Rich Sites Ideal for galleries, portfolios, landing pages, and visual storytelling sites where images contribute heavily to page weight. Bulk optimization and higher compression modes help significantly reduce page size. ⚡ Performance-Focused WordPress Sites Great for site owners focused on speed, Core Web Vitals, and PageSpeed audits. Optimized images and modern formats like WebP help improve loading performance across desktop and mobile. 🏗️ Existing WordPress Websites Useful for established sites with large media libraries. Previously uploaded images can be optimized in bulk without re-uploading or rebuilding content. 🌍 Sites Without a CDN A reliable solution for websites that don’t use a CDN. All image optimization and WebP conversion happen locally inside WordPress, with no external services or API keys required. 🧩 Custom Themes & Advanced Setups Suitable for custom WordPress themes and advanced setups where images live outside the Media Library. Custom folder optimization allows full-site image optimization beyond standard uploads. What Users Say About Robin ★★★★★ Excellent plugin “I use Robin on all my WordPress sites. It’s easy to set up, effective, and really helps reduce loading times.” ★★★★★ Great plugin “A free image optimization plugin without image limits? Really impressive.” ★★★★★ Don’t waste time on others “This has to be the best free optimizer I’ve tried. Fast, simple, and very efficient.” ★★★★★ Great plugin. Nice work “Saves a lot of time and reduces disk space usage.” ★★★★★ Thank you Robin Hood “I tried many other image compression options — this one works best.” Support Need help? Open a new thread in the Support Forum, and we’ll be happy to assist. 📘 Documentation Discover how to make the most of Robin with our detailed and user-friendly documentation.