You can select your preferred file size from the right side dropdown menu, as shown below. 

Currently, you can filter sizes between 16 and 512 pixels. You can preview how the graphics will look like, as they automatically resize when you choose a different size. 

If you click on an item, a window with options for downloading will show. If you want to download a PNG format you can choose the size like in the screenshot below. Again, by clicking on the different options the preview of the graphic will be automatically resized according to the chosen size. 

A larger variety of sizes is available by clicking on the More sizes button. 

If you click on the item again, you will get to the item details page, where you can choose the size on the same principle. We recommend SVG format for larger images or when you want to keep the quality when resizing.