Plugin Directory

Kraken Image Optimizer

This plugin allows you to optimize your WordPress images through the Kraken API, the world's most advanced image optimization solution.

This plugin allows you to optimize new and existing WordPress image uploads through Kraken Image Optimizer's API. Both lossless and intelligent lossy optimization modes are supported. Supported filetypes are JPEG, PNG and GIF. Maximum filesize limit is 16 MB. For more details, including detailed documentation and plans and pricing, please visit Kraken.io.

Get your FREE account with us

Sign up for your FREE Kraken.io Account and try out our plugin and the rest of our features now, including:

  • API Access, with dozens of ready-to-use libraries and modules
  • Web Interface PRO with Image Resizing and sync-to-Dropbox
  • URL Paster
  • Page Cruncher
  • Optimization Stats and History
  • ...and more.

About the plugin

  • You can use your Kraken API key and secret on as many sites/blogs as you like. We have no per-site license.
  • All images uploaded throught the media uploader are optimized on-the-fly. All generated thumbnails are optimized too.
  • All images already present in the media library can be optimized individually, or using the Bulk Action menu "Krak 'em all" feature.
  • This plugin does not require any root or command-line access. No compilation and installation of any binaries is necessary.
  • All optimization is carried out by sending images to Kraken.io's infrastructure, and pulling the optimized files to your WordPress installation.
  • To use this plugin, you must obtain a full API key and secret from https://kraken.io/plans. Our free account comes with a limited quota for testing our premium features, including this plugin.
  • Works great with WPEngine hosted blogs, including the staging area.
  • Since version 1.0.4, the plugin will work with local WordPress installations; the client site does not need to be published on the web.

★★★★★ 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 travelmemo.com now sports Google's 'mobile friendly' tag for mobile searches" — Walter Schaerer

★★★★★ Perfect solution to speed up site! "I love this plugin! All the questions I had are quickly responded to and I see a huge saving with image size without losing the quality. I highly recommend this plugin!" — ezone69

Once you have obtained your credentials, from your WordPress admin, go to the Kraken.io settings page. The from there you can enter your API credentials, and select your optimization preferences. Once you have done this, click on Save. If everything is in order, it will simply say "settings saved" and give you a reassuring green tick that your credentials are valid. You can now start optimizing images from within Media Library. Any image you upload from now on, through any of the media upload screens will be optimized on-the-fly by Kraken.

For advanced users, there is a third party WordPress Command Line Interface (CLI) tool to allow image optimization from the command line, or by using cron. For details, visit: https://github.com/tillkruss/wp-cli-kraken

Features on the way

  • Optimize images directly to Amazon S3.
  • Optimize entire media library in one click.
  • Optimize your currently active theme.
  • WordPress Multisite support.

Please send bug reports, problems, feature requests and so on to support (at) Kraken dot io, or directly to the author of this plugin.

Connect with Kraken.io

Requires: 3.0.1 or higher
Compatible up to: 4.2.5
Last Updated: 7 months ago
Active Installs: 10,000+


4.6 out of 5 stars


0 of 4 support threads in the last two months have been resolved.

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