How to use Image Compressor
- Select your files in the Images field.
- Set Quality for JPEG and WebP output.
- Choose an Output format, or leave it on Keep the original format.
- PNG output ignores Quality. To shrink a PNG, open More options and set PNG colors to 256 or fewer; Full color (lossless) keeps every color but rarely saves space.
- Select Compress, then download the ZIP.
Example: Image Compressor
Re-encode a PNG photo as a smaller JPEG.
Options
- Quality
- Used for JPEG and WebP output only, where it is lossy. PNG ignores it.
- PNG colors
- Its default of 256 colors switches a PNG to palette quantization, which is what actually shrinks it and can change colors and smooth shading. Full color (lossless) keeps every color.
- Output format
- Keep the original format writes each file back as it was. JPEG and WebP use lossy compression. Compare the file size and visible detail for your own images.
- Maximum longest side (pixels)
- Zero keeps the original pixel size. A number such as 1600 scales the longest edge down to that many pixels, and images are never enlarged.
Supported inputs and limits
Where your input is processed
This tool processes your input in this browser. Your text and files are not uploaded to UseFreeTools. Check this tool's limits for anything it may save on your device.
Why a lossless PNG re-encode rarely shrinks a file
PNG is already a compressed, lossless format. Its rows are filtered and then compressed with the DEFLATE algorithm, so encoding the same pixels again with the same method lands on roughly the same bytes and can even add a few. The setting that really changes PNG size is the number of distinct colors: at 256 or fewer the image is rebuilt as a palette image, where each pixel is an index into a color table instead of a full color. Gradients and photographs can show banding afterwards, which is why Full color is the safe option.
Questions about Image Compressor
Why is my PNG the same size after compressing it?
At Full color (lossless) the same pixels are compressed the same way, so the file lands on roughly the same number of bytes. Lower PNG colors to 256 or fewer, or set Maximum longest side, to get a real reduction.
Should I choose JPEG or WebP?
Both are lossy at the quality you set. Compare the outputs at your chosen settings. JPEG may work in older software that cannot open WebP.
Does compressing remove the location data in my photo?
Yes. A re-encoded file is written fresh without the original EXIF block, so camera details and GPS coordinates do not survive. Keep the original if you need them.
Why did my large PNG refuse to reduce colors?
Palette reduction is limited to 16 megapixels of output so the browser tab stays responsive. Set Maximum longest side to 4000 pixels, which brings a 20 megapixel image back inside the limit.