Exclaimer signature templates have size and volume limitations to keep the signature file size low and ensure maximum performance.
The following table lists the limitations within Exclaimer for signature templates:
| Feature or function | Maximum limit |
| Image file size | 300KB |
| Custom font file size | 1MB |
| Elements in one signature template | 250 |
| Images in one signature template | 50 |
| Elements in one container (such as a table or table cell) | 20 |
Some design choices are not available in the Exclaimer Signature Designer. Select an option below to learn about design limitations and possible alternate methods.
Only the Social Media Icon or Social Media Group elements can use rounded corners. These are on the social media icon images - to apply a rounded corner to your social media icon(s), use the Corner Radius property in the Properties pane. For more information, see Working with the Social Media Icon signature element or Working with the Social Media Strip signature element.
Other images, lines, and/or tables and cells cannot have rounded corners.
You can create the look of rounded corners by adding images of rounded corner shapes to your template, either by using the Image/Logo element, or by adding a background image.
You cannot add gradients while coloring items (including background colors) in the Signature Designer. You can add an image of a gradient, such as a background image, to create a gradient color effect.
The Signature Designer cannot alter the shape of an uploaded image, but you can upload images of any shape to have in your signature template. This includes the User Photos feature, the Image/Logo element, and background images. For example, if you want to have a circular image in your template, you must upload an image file for an image that is already circular.
The design of an Exclaimer signature template is structured with square and rectangular sections, formed by tables and groups. These sections form the layout of your design. Due to this structure, you cannot overlap elements across table cells or groups. This includes overlapping different background colors - as cells can only be colored one color at a time, it is not possible to then place foreground elements in a way that overlaps two cells. 
An example of using different colors in cells to make a two-tone background, shown in the signature template in the Signature Designer. All elements must be contained in a cell or group and so they cannot overlap each other or backgrounds.
You can achieve an overlapping look by uploading a background image containing the design you want your elements to overlap, then adding your elements and arranging them over it.