Compress Images to a Target Size
Set a maximum size for every image, or use a quality preset. Compress JPG, PNG, WebP, and more in batch with verified downloads. 100% browser-based. Zero uploads.
Drop your images here
or click to browse —select multiple images at once
Supports JPG, PNG, WebP, GIF, BMP —Up to 20 MB each, 30 images
0 images selected
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Compression Settings
Compression mode
Choose a flexible quality preset or set a strict per-image size limit.
Low
Best quality, slightly smaller. Ideal for photography and print.
Medium
RecommendedGreat balance. Perfect for web, social media, and documents.
High
Maximum compression. Best for email and quick sharing.
Maximum size per image
Each completed image is verified against this limit before download. Images already below it are left untouched.
500 KB
per image maximum
Available from 20 KB to 20 MB for each image.
Common upload limits
Target mode preserves the current dimensions whenever possible, then reduces them proportionally only when quality alone cannot meet the limit.
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How it works
Three simple steps —everything happens in your browser.
Upload your images
Drag and drop or click to select multiple images. JPG, PNG, WebP, GIF, and BMP are supported.
Choose a quality preset or target size
Use Low, Medium, or High, or choose a maximum size for every completed image.
Verify and download
Target-size results are checked before individual download or ZIP export.
Why choose ToolKnit for Image Compression?
100% Private —No Server Uploads
Your images never leave your device. All compression is done locally using the Canvas API. No data is sent to any server —ever.
Batch Processing
Compress up to 30 images per batch. Files are processed one at a time to control memory, then packaged into a convenient ZIP download.
Verified Target Size
The final encoded bytes are checked before download. Quality is adjusted first, with proportional resizing only when needed to meet the limit.
Optional Resize
Optionally downscale images that are too large. Perfect for preparing web-ready images or meeting email size limits.
Pro Tips
- ● Use a target-size preset such as 200 KB or 500 KB when a website sets an upload limit.
- ● Completed target-size images are always at or below the selected maximum, not just approximately smaller.
- ● Transparent PNGs stay transparent. Enable Smart smaller format only when WebP is accepted by your destination.
- ● A ZIP contains each successful image at its limit; archive overhead can make the ZIP itself slightly larger.
Frequently Asked Questions
Yes. Choose Compress to a target size, select a common limit such as 100 KB, 200 KB, or 500 KB, or enter a custom maximum. Every completed image is checked before download.
Yes for completed target-size results. ToolKnit verifies the final encoded bytes and includes a file only when it is at or below your chosen maximum. An image that cannot meet the limit, such as an animated GIF that must keep its frames, is clearly excluded.
Transparent PNGs keep transparency. By default PNGs stay PNG; you can opt into WebP for a smaller compatible output. Animated GIFs are kept unchanged to avoid losing frames, so they cannot be claimed as target-size results when they exceed the limit.
Yes. The selected maximum applies to every image in the batch individually. Successful images can be downloaded as a ZIP; the ZIP file itself may be slightly larger because of archive overhead.
No. Compression happens entirely in your browser using the Canvas API. Your images are never uploaded anywhere, and the tool works offline once loaded.