Image Resizer for Windows is a utility that lets you resize one or more selected image files directly from Windows Explorer by right-clicking. It’s a handy tool that I install on every Windows machine I own, and it’s compatible with Windows 8.
Supported File Types
By default, the tool handles these image formats: bmp, dib, gif, ico, jpe, jpeg, jpg, png, tif, tiff, and wdp.
Download: Image Resizer on CodePlex