PXLTools

Image Compressor

Reduce image file size while keeping quality

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Drop images here to compress
JPEG, PNG, WebP — up to 50 MB each, 20 files max

How to use Image Compressor

  1. Drop images into the upload zone (or click to browse).
  2. Adjust the quality slider — lower values mean smaller files but lower image quality.
  3. Optionally change the output format (WebP usually gives the best compression).
  4. Compare before and after using the quality slider. Each image shows its savings.
  5. Download individual images or all at once as a ZIP file.

How does image compression work?

Image compression reduces file size by removing data the human eye is unlikely to notice. JPEG uses perceptual quantization to discard high-frequency details. WebP and AVIF use similar but more advanced techniques, achieving smaller files at the same visual quality.

Quality settings determine how aggressive the compression is. A quality of 100 means almost no loss; quality 50 can cut file sizes dramatically at the cost of visible artifacts. For most web images, 75-85 is the sweet spot — files are 40-80% smaller than the original with barely any visible difference.

PNG compression is lossless, meaning the output looks identical to the input. The savings come from better encoding rather than discarding data. Converting PNG to JPEG or WebP usually shrinks files much more, but PNG remains best for images with transparency or hard edges.

Frequently Asked Questions

How much can I reduce file size?
Typical JPEG compression at quality 80 reduces file size by 40-80% with minimal visible quality loss. WebP usually beats JPEG by another 25-35%. PNG compression is more limited because PNG is lossless by default — significant savings require converting to a lossy format or reducing color depth.
Will the quality actually drop?
For JPEG and WebP: yes, but at quality 75-90 the difference is usually invisible to the human eye while the file size drops dramatically. Use the before/after comparison slider to see the difference on your specific image. For images that will be printed, use quality 90+.
What is the max file size I can compress?
Up to 50 MB per image and up to 20 images per batch. Files larger than this are rare and your browser would struggle to handle them anyway — for bigger files, consider a desktop tool.
Are my images uploaded to a server?
No. All compression happens in your browser using the Canvas API. Images never leave your device.
Which format should I use?
WebP for the web (best compression, widely supported since 2020). JPEG for photos when WebP is not an option. PNG for images with transparency or sharp edges like logos and screenshots.