Resize, convert and rename thousands of image files in batch mode with ImageSize. Resize your images to reduce their size on disk and optimise them for a specific usage like sending via email or posting online. Also, if your original image files are poorly named, you can use ImageSize to give them meaningful names so they are easier to find and identify.

But here is what ImageSize has to offer:

* Resize your images in batch mode
* Use either pixels or percents to define the new dimensions
* Keep the original aspect ratio of your images
* Resize portrait images more efficiently by considering that width is always the largest dimension
* Resize your images by fixed width or height
* Resize your images by fixed width and height
* Change the DPI of your images in batch mode
* Convert and rename your images in batch mode
* Keep the EXIF info and creation date of your original images
* Output formats: JPG, JPEG, JPE, JP2, JPX, PNG, TIFF, TIF, GIF, BMP, HEIC, HEIF
* Save the resized images in a folder of your choosing

So purchase ImageSize today and tasks that usually take hours will only take seconds to complete.

What’s New

Version 1.2

- Support for dark mode in macOS Mojave
- Resizable app window
- All compatible image files can now be opened directly into the app using the Open With option from the macOS contextual menu
- Added the option to not enlarge images that have smaller dimensions than the ones set by the user
- Change the DPI of your images in batch mode
- Added support for the HEIC and HEIF image formats
- Force the output names of your images to be uppercase or lowercase
- Minor bugfixes and user interface improvements

Ratings and Reviews

4.5 out of 5
47 Ratings

47 Ratings

paleohebrew ,

Selectively resizing out of thousands of photos

I'm new to Mac and needed something to resize large numbers of sports photos. It does a good job and is easy to figure out how to make it work..... HOWEVER, since I pick and choose out of thousands of pictures in a folder, if I happen to click in the wrong spot, it looses all my selection unless I am constantly hitting "OPEN."

Itzawrap ,

Makes Quick Work of Resizing

This is just what I needed to quickly and intuitively resize thousands of photos I had processed in Lightroom and exported at full resolution. But then found out I needed them to be smaller for another use.

The photos are organized by topic and date so it would have been a real pain to go back into Lightroom and re-export at the smaller image size.

Yes, I must go through each folder catagory one by one but the Image Size window is easy to use, the conversion sizes are easy to set and file name changed to show the resize as well as output folder is selectable. Just remember to create new folders outside the app before you do your batch resizing.

Not hard to figure out and a massive time saver.

Oak Norton ,

Perfect easy to use bulk resizer

I needed a tool to bulk resize images and keep the aspect ratio. Thankfully I found this one and it did a great job without the need for reading any instructions. Great reduction and great quality compression.


Day 1 Solutions SRL
8 MB

OS X 10.10 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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