RoundIt

RoundIt is an easy-to-use software utility that can help you make the edges of your photos round. It offers support for JPEG images and can handled by all types of users, whether they have previous experience with photo processing tools or not.

Simple setup and interface

The setup operation is fast and shouldn't give you any trouble, thanks to the fact that it contains only familiar options. An important aspect worth noting is that it requires .NET Framework installed.
Once it's over, you are greeted by a clean and intuitive interface made from a standard window with a clear-cut structure, which contains an embedded preview frame for images.

Preview and process JPEG images in bulk

Rounded edges can be added to JPEGs either in single or batch mode, so you can process multiple files at the same time to speed up the workload.
You can preview photos with rounded edges in the main application window, adjust the radius level by entering a percent value or moving a slider (default is 10%), leave the background transparent or select a color, as well as leave the image without borders or apply single-line borders and specify the line width.

Add background colors and borders

The new modifications can be overwritten to the original files. Alternative, you can save them to new files by indicating the output directory (same as the source or different). Lastly, RoundIt gives you the possibility to either leave the file type unchanged, or convert the new files to PNG or GIF format.
Apart from the fact that you can copy images to the Clipboard and paste them into the main frame to prepare them for processing, there are no other notable options available here.

Evaluation and conclusion

Everything worked smoothly in our tests, since the tool didn't freeze, crash or prompt error dialogs. It carried out bulk processing jobs swiftly while remaining light on system resources consumption.
To sum it up, RoundIt may not contain rich features and customization preferences, but it offers a simple solution to adding rounded edges to images and saving them with different file extensions.