You might be converting images from one format to another for various reasons and also there are many freeware tools to convert and resize images. XnConvert is another free tool for converting images from one format to another, but it comes loaded with features like ability to enhance images before converting, support for more than 400 formats etc. You can resize, add a watermark, change contrast, brightness or gamma, apply filters and many other changes to images.
The application interface is very neat and arranged in tabs. You can add files and also folder of images.
The Actions tab lets you to select the actions you want to have on the image, you can select multiple actions, there are various settings and filters available for selection. It supports more than 400 file formats (jpeg, tiff, png, gif, camera raw, jpeg2000, WebP, OpenEXR etc).
The output tab has options to set the folder for saving the images and other application settings. Overall XnConvert is a nice free tool to edit and enhance your images.