Image compressor for macOS and Windows

Main Features:

Optimize a folder at a time

Drag in hundreds of photos or a whole folder, choose a mode, and Compressa works through the set in one pass. Smaller files are handled first, so results start appearing right away.

Five compression modes

Auto for a simple quality slider, Target File Size to hit an exact KB or MB, Reduce to % for a share of the original, Lossless to re-pack without changing a pixel, or Smart to find the smallest size that still looks the same.

Smart mode, on by default

Smart compression compares each result to the source with an SSIM measurement and stops the moment the difference would be invisible. Photos get a JPEG or WebP quality search; flat graphics get a palette that looks identical.

Modern and legacy formats

Read and write JPEG, PNG, WebP, HEIC and AVIF, and open BMP, GIF, TIFF, ICO and SVG for conversion. Keep a file in its format and just shrink it, or convert an aging JPEG to WebP or HEIC to save even more.

Live before/after preview

A split view with a draggable divider shows exactly what the compression does, next to the estimated output size, so you judge the trade-off before anything is written to disk.

Resize and convert in one pass

Scale by width, height, the long or short side, or a percentage while you compress. Images are only ever made smaller, never enlarged.

One-click presets

Web, Email, Social, Archive and Lossless presets set the format, mode and resizing in a single click. Save your own combination as a custom preset for work you repeat.

Watch folders

Assign a folder and Compressa optimizes new images automatically as they arrive, so a screenshots directory or an incoming network share stays optimized without you opening the app.

Metadata and originals under your control

Keep or drop EXIF date, camera, GPS and copyright tags separately, and strip ICC color profiles for the leanest file. Every source is backed up before it is replaced, and the output is never larger than the original.

Compressa