Presentation builder will support any standard image format that a browser can render
- For example, .jpg, .png, .gif or .webp
- .jpg is usually the most efficient file type
- .png is required if you need transparency
Sizing Your Image
Our Presentation builder will scale your images cale your images as best it can depending on your screen resolution and the window(browser or installed software) size and shape. This is more about the default screen size and resolution than it is about the Custom Presentation tool.
Ideally, there are two Modes to consider 4:3 ratio and 16:9 ratio
Image dimensions best for each
4:3 640x480 pixels
16:9 1080x1920 pixels
But I would take it one step further. Even if you have an image that fits these parameters, resizing your screen can cause some issues in the presentation tool. It can even be an issue if you have changed your default windows font controls and text sizes. I usually recommend trying to drop the image in first. The guides that are preview page (green =4:3 purple = 16:9) will give you a clue how the image will render so long as the page fits into those ratios.
If you are having trouble with an image I typically recommend using a program like PowerPoint to set the Image on a slide that is natively 16:9 and saving that slide as an image, this will set a wider margin and will resize easier if you are using the presentation window in an unusual size.