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/ Kraken.io Image Optimizer

Kraken.io Image Optimizer

By Kraken.io

Performance & Optimization / Image Optimization & Compression

Reviewed by Omar Dabbas

Trusted WordPress expert with 20+ years of experience evaluating plugins for the WP ecosystem.

Kraken.io Image Optimizer Review - In-Depth Analysis

Optimize and resize your WordPress images using the Kraken.io API. Supports JPEG, PNG, and GIF formats. Offers both lossless and intelligent lossy optimization.

Performance Overview

WPS Score

7.06/10

User Rating

4.5/5 (based on 119+ reviews)

Active Installations

10,000+

Update Frequency

Average It is calculated using the weighted average of same category plugins.

Security Score

5 / 10 (Medium Risk) It is calculated using the weighted average of all versions.

What It Does

This plugin allows you to optimize and resize new and existing WordPress image uploads through Kraken.io's API. Both lossless and intelligent lossy optimization modes are supported. Supported filetypes are JPEG, PNG and GIF (including animated GIF). Maximum filesize limit is 32 MB. Even when using Kraken.io's lossy optimization, our system goes the extra mile to ensure that the results are of high quality, every time.

You can use your Kraken.io API key and secret on as many sites/blogs as you like. We have no per-site license. All images uploaded through the media uploader are optimized on-the-fly. All generated thumbnails are optimized too. The main image upload can be optionally resized, which is useful for preventing user uploads with unnecessarily large dimensions.

When restricting the maximum dimensions of the main image using the resizing feature, the resulting image is enhanced using various advanced techniques to help prevent downsample artifacts and produce a sharper result. You can optionally preserve one or more of the Date, Copyright, Geotag, Orientation, Profile EXIF metadata tags. Images can be automatically oriented according to their EXIF Orientation value.

Comparing to Alternatives

Kraken.io Image Optimizer is a popular image optimization plugin with several direct competitors offering similar features.

Top alternatives

Strengths

High image compression efficiency saving significant storage space
Supports multiple image formats including WebP and AVIF
Offers both free and pro versions with advanced features in pro
Generally positive user ratings with 84% five-star reviews
Integration with WordPress for easy image optimization

Weaknesses

Customer support is reported as poor or non-responsive
Subscription cancellation issues reported by users
Bulk image optimization functionality has limitations
Security vulnerability fixed only in recent versions

User Sentiment Analysis

With a strong majority of 5-star ratings, users appreciate the plugin's effectiveness, but a notable minority report serious issues, especially regarding support and subscription management.

Positive highlights

"Just saved a few GB from my websites and the support service is great." - emldesign
"Quick and easy to use for image optimization." - general positive feedback
"Effective in reducing image sizes significantly." - multiple users

Common complaints

Unresponsive and poor customer support
Subscription cancellation difficulties and billing issues
Bulk image optimization does not meet expectations
Plugin updates and maintenance appear neglected

Weaknesses

Customer service is often described as non-existent
Some users report poor quality results
Plugin has had security vulnerabilities in the past

Who Should Use This?

Best for

Users who need efficient image compression with support for modern formats and are comfortable managing subscriptions carefully.

Not ideal for

Those who require responsive customer support, bulk image optimization at scale, or are concerned about past security issues should consider alternatives.

Pricing & Value

Free version includes

The free version offers basic image optimization features suitable for small to medium websites.

Pro version

Premium features include higher compression limits, bulk optimization, advanced format support, and priority support.

Final Verdict

Kraken.io Image Optimizer delivers strong image compression capabilities with support for modern formats and a generally positive user experience. However, significant concerns about customer support, subscription management, and past security vulnerabilities may deter some users.

For those prioritizing effective image optimization and willing to navigate potential support challenges, Kraken.io remains a viable option. Users needing robust support and bulk processing might find better alternatives among its competitors.

Other Notable Features

Here are a few other notable features of this free Kraken.io Image Optimizer plugin.

Compress Images

Image Optimizer

Image Resize

Screenshots

FAQ

Yes you can. All of our plans require that you first create your free Kraken.io account. No credit card is required, and we give you free testing quota of 50 MB, with which you can test all the features we offer, including this plugin.

Additionally, if you would like to test the performance and results of Kraken.io Image Optimizer, you can try the free Web Interface at https://kraken.io/web-interface which does not require any registration.