This might be a little bit more than you're asking for, although I would try FastStone Image Viewer. Not only can it convert as many images as you want into many formats but it can view, sort, basic image edit, slideshow, batch rename, and much more. It's free and very reliable with little confusion. I use it a lot.

DDS Converter is what I used when needing to convert image for level textures. It's free and can convert as many images as you like with lots of option settings for the images. It can do supports lots of file types.

Actions MenuClick the arrow to bring up the menu and choose New Set. An action set can contain several actions. If you've never created actions before, it's a good idea to save all your personal actions in a set. Give your new Action Set a name, then click OK. If you want to know more details please visit here https://onlineconvertfree.com/converter/images/

In the dialog box, simply select the set and the action you just created. For the source, choose the folder that contains the images you want to process. For the destination, choose another folder for Photoshop to output the rotated images. (You can choose "Save and Close" to have Photoshop save them in the source folder, but I don't advise it... it's too easy to make a mistake. It's much safer to use two folders and then delete the original files after you've made sure your batch processing was successful.) For errors you can either have the batch proccess stop, or create a log file of the errors. When you hit OK, you can just sit back and watch while Photoshop does all the work for you!

Once you have an action and you know how to use the batch command, you can use it anytime you have several photos you need to rotate. You could even do an another action to resize a folder of images.