Mihov Image Resizer is a freeware which can be used to batch resize images in bmp, gif, and jpg picture formats. It can make any kind of images smaller or bigger - whichever you need at the time. converting pictures between different graphic formats. It can change from bitmap to JPEG or GIF, from JPEG to GIF or from GIF to JPEG. Again, this can be made in batch mode. That means that you will only have to select the images and the program will do the rest for all selected images.
Mihov Image Resizer is also a perfect utility for creating thumbnails, so you can put them on your home page for faster loading or send pictures with smaller size to family and friends by e-mail.