Image Compressor

Compress a batch of images locally

Choose or drop up to 10 images, adjust quality from 10% to 100%, and start compression. Each file may be at most 10 MiB. Processing uses the browser's canvas encoder; your image content is not uploaded by this tool. You can download files individually or download the completed results as a ZIP.

A measured example, not a size guarantee

In a local Chrome check on 2026-10-27, the site's public android-chrome-512x512.png fixture produced these results:

The 80% result was about 81% smaller for this particular image. Results vary with image content, source encoding, quality, browser, and encoder implementation. The same quality number does not imply the same visual quality or reduction for every file.

Steps

1. Add supported images, staying within the file count and per-file limits.
2. Select a quality level. Keep the originals until you have reviewed the new images.
3. Start compression and wait for each file to finish.
4. Inspect the output size and visual result, then download one file or the ZIP.
5. Change quality and compress again if the result is unsuitable. A new slider value alone does not regenerate previous results.

A file can be below 10 MiB yet contain many pixels and require substantial canvas memory. Processing a smaller batch can help when a mobile browser runs out of resources.

Output format and transparency rules

• PNG inputs retain PNG at quality 90% and above. Below that threshold, the encoder uses JPEG, which cannot preserve alpha transparency.
• WebP inputs use WebP at 99–100% quality and otherwise use JPEG.
• Other browser-decodable inputs are re-encoded through canvas, usually to JPEG. A GIF that is re-encoded becomes a static frame rather than an animated GIF.
• At quality 95% and above, if the re-encoded result is not smaller, the tool retains the original file instead. That branch also retains the original format and metadata.

There is no independent output-format selector or target-file-size control. Download extensions follow the actual output MIME, including inside the ZIP. These are encoder settings, not a guarantee of lossless compression.

Choosing a setting and checking results

For a transparent logo, preserve PNG transparency and inspect edges against both light and dark backgrounds. For a photograph, compare gradients, faces, fine text, and sharp edges at the size where the image will be used. A lower quality may save more bytes but introduce visible artifacts.

The tool does not resize the pixel dimensions or guarantee a specific KB target. It is not a reliable metadata-removal workflow, particularly when the original-file fallback is used. Keep a separate original when metadata or image quality matters.

Troubleshooting and related tools

If an image is not added, check its count, size, and file type. Browser decoding support determines which image encodings can be processed; this is not a universal converter for all image formats. If compression fails on a large photo, try fewer images or a lower-resolution source.

Use the circular cropper to make a transparent circular avatar. Use image to Base64 when the resulting file is small enough for a text-based workflow.