If you need to compress images, reduce image file size on Mac, we recommend ImageOptim – the best free image compression for Mac. It is a front-end (GUI) for the following applications:
- and PNGOUT.
All of them are FREE.
If you run ImageOptim to compress images on Mac, the image compressor app runs them and automatically selects the smallest file.
How to compress images on Mac using ImageOptim?
Duplicate the source images first as the compressor will overwrite them during the compressing process. Note that it support popular image formats like JPG, JPEG, PNG, TIFF and many more. It however doesn’t support the new HEIC format. If you want to compress the iPhone iPad photos in HEIC format, you need to convert the HEIC images to PNG, JPG or TIFF format on Mac.
Download the free image compression app for Mac if not yet. Run it from the Launchpad. Drag and drop PNG or JPEG files or directories from Finder onto main table view in ImageOptim’s window. You can also drop files onto ImageOptim’s Dock icon. Wait until ImageOptim finishes. Files will be overwritten with smaller versions. Unoptimized versions will be moved to Trash.
In the file list of the image compressor program, you will see an icon before each image file.
- Green Checkmark: Image has been optimized successfully.
- Green X: Everything went fine, but image couldn’t be optimized any further.
- Gray star: Optimization of this file is in progress.
- Gray dots: File is queued to be optimized after other files are finished.
- Orange exclamation mark: There was an error during optimization. You’ll find explanation by running