How To: Mass-Compress / Mass-Resize Image Files

This guide will show you how to compress image files to be ~200 kB JPEG files, or mass-resize images, suitable for emailing or uploading to sites.

1. Download Irfanview (free! )
2. Install it (default settings are fine, but I generally don’t like installing Google Toolbar)
3. Run it (Start => Programs => Irfanview => Irfanview #.##; where #.## is the version number)
4. Press “B” (or go to File => Batch Conversion/Rename)
5. In the top-right area of the new window, navigate to the folder with all of the images you want to compress
6. Select the pictures that you want to compress/resize and click on the “Add” button, OR click on “Add All” to add all of the images in the current folder
7. On the left-hand side of the window, ensure:
   1. “Work as” is set to “Batch conversion”
   2. “Output format” is set to “JPG – JPG/JPEG Format” (doesn’t have to be JPG, but for this tutorial, I’m using JPG)
   3. “Use advanced options (for bulk resize…)” is ticked
8. Click on the “Options” button, change the “Save quality” to 90 and click on OK (note: if you only want to resize images, you’d generally set the “Save quality” to 100)
9. Click on the “Advanced” button
   1. Tick “RESIZE”
   2. Tick “Set long side”
   3. Enter a size and select a unit of measurement (e.g. 800 pixels)
   4. Tick “Preserve aspect ratio (proportional)”
   5. Tick “Use Resample function (better quality)”
   6. Click “OK”
10. We’re almost done! Next thing to do is choosing where all your modified image files will be stored. Under “Output directory for result files”, you can choose to click “Browse” and select a folder. What I like to do is click on “Use current (‘look in’) directory”, which will set the path to be exactly the same as the folder all of the original images are stored in. After clicking on that, in the path text box I manually type add “compressed” to the end.
11. After settling on where to save all the modified images, click on the “Start Batch” button