Automatically compress and convert your images to modern formats (WebP, AVIF). Get a perfectly optimized image every time and speed up your website.

Toolszu

Toolszu Image Optimizer

Toolszu Image Optimizer is a lightweight WordPress image compression, resizing, and WebP conversion plugin designed for content writers, bloggers, and …

NerdCow

Make your website faster than ever with TIO’s smart optimization.
Upload your images like you’ve always done before, and we’ll handle the rest. The Image Optimizer compresses your image and converts it to a modern file format. The result is the lightest image possible, without losing the quality.
Already have a media library full of images? The new Bulk Optimize tab works through your existing uploads one at a time, with live progress, ETA, and pause/resume/stop controls — no need to leave it running in the foreground.
Why choose our plugin?
The Image Optimizer uses smart optimization parameters tuned specifically for website images. It’s designed to be a simple companion that gives you the perfect image every time. We decide on the perfect balance of size and quality for your uploaded image. TIO automatically converts your new uploads to the best format (including modern formats like WebP and AVIF), applies lossless conversion or uses lossy compression settings that don’t affect the quality.
It’s perfect for small marketing teams who don’t have the time and know-how to optimise images manually and busy agencies who can’t afford the time to do it manually at scale.
We developed TIO to solve our own frustration with image optimizers. As a result, we were able to achieve results up to 35% file size reduction compared to other compressors. Going the extra mile helps ticking off the Google PageSpeed insights image checks, especially those for next-gen image formats.
How it works?
You upload your images as you normally do — one by one or in bulk, either way is fine. You can do it via the WordPress media library and by uploading directly into your pages.
We categorise what’s in the image to apply the right optimization settings. We use suitable compression and file format conversion, as well as remove unnecessary metadata.
As an example, screenshot compression makes sure to not sacrifice text sharpness, while plain illustrations with low colour depth use more aggressive compression since it won’t affect the quality nearly as much.
We optimise the source file, so WordPress thumbnails come pre-optimised as well.
Bulk Optimize for existing media
Open Tools → The Image Optimizer → Bulk Optimize, hit Scan, then Start. The plugin processes one attachment per tick so your site stays responsive, shows live counts for done / savings / credits left, and gives you an ETA once it has enough data. Pause and resume any time — progress is saved server-side, so closing and reopening the tab picks up exactly where you left off.
Bulk runs preserve the original file format (JPG stays JPG, PNG stays PNG), so URLs in your posts and pages never break. Thumbnails are regenerated locally — you’re charged one credit per attachment, not one per thumbnail size. Images that can’t be optimized (too small, unsupported format, missing file, oversized, or already smaller than we can compress) are clearly labelled in the Media Library so you can see at a glance what’s been done.
Next-gen delivery (WebP & AVIF)
Optimizing an image now also creates WebP and AVIF copies of it — and of every thumbnail size — and serves them automatically to browsers that support them through a <code><picture></code> tag. The result is faster pages and a clean pass on Google PageSpeed’s “Serve images in next-gen formats” check. Your original files and their URLs never change (browsers that can’t take the modern formats simply get the original), it’s all part of the same one-credit-per-image optimization with nothing extra to switch on, and the copies are tidied up automatically when you delete an image. This applies both to new uploads and to your existing library when you run Bulk Optimize.
Supported file formats
The only excluded file format is GIF. We support all other file formats that WordPress allows, including HEIC.
Try it for free
TIO allows you to generate one license key with 50 free image credits per website. That’s enough to test a few core pages and measure the impact.
<ol>
<li>Get a free license key at <a href="https://theimageoptimizer.com/key" rel="nofollow ugc">theimageoptimizer.com/key</a></li>
<li>Paste the key in Tools > TIO Image Optimizer</li>
<li>Upload images as usual — they are compressed automatically</li>
</ol>
Credit restoration for peace of mind
Uploaded an image by mistake or we didn’t optimise it to your liking? You can reclaim the credit straight from the WordPress Media Library, subject to our <a href="https://theimageoptimizer.com/terms" rel="nofollow ugc">Terms</a>.
And if we notice that your image was already optimal, we won’t charge a credit in the first place — nothing to reclaim there!
External Service Disclosure
This plugin relies on The Image Optimizer API, a third-party service hosted at <code>api.theimageoptimizer.com</code>, to compress images. When you upload an image with auto-compress enabled, the plugin sends the image file and your site URL to this API. The API returns a compressed version of the image, which replaces the original in your media library.
No data is collected or stored beyond what is needed to process the compression request and manage your credit balance.
<ul>
<li>Service website: <a href="https://theimageoptimizer.com" rel="nofollow ugc">theimageoptimizer.com</a></li>
<li>Terms of Service: <a href="https://theimageoptimizer.com/terms" rel="nofollow ugc">theimageoptimizer.com/terms</a></li>
<li>Privacy Policy: <a href="https://theimageoptimizer.com/privacy" rel="nofollow ugc">theimageoptimizer.com/privacy</a></li>
</ul>

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