Therefore, we offer Landscape, a site that offers the ability to resize images for each social network.

This website allows you to cut the size of the images you want, just by specifying the size of the social network you want. It's an automatic site to resize images targeted to social networks.

To use it, you do not need to register and it is completely free, in this sense, go to the site and you will be asked to drag the images you want to edit to the interface. When you upload the image, all available networks will appear where you can edit images for networks:
YouTube
You can try it from the following link: sproutsocial