Office Add-in UI elements

You can use two types of UI elements in your Office Add-ins:

  • Add-in commands
  • Custom HTML-based interfaces

Add-in commands

Commands are defined in the add-in XML manifest and are rendered as native UX extensions to the Office UI. For example, you can use add-in commands to add buttons to the Office ribbon.

An image showing add-in commands and custom HTML UI elements in an add-in

Currently, add-in commands are only supported for mail add-ins. To learn more, see Add-in commmands for mail.

Excel, PowerPoint, and Word have predefined entry points for task pane and content add-ins on the Insert tab in the Office ribbon. Custom command functionality for content and task pane add-ins will be available soon.

An image that shows the Insert Tab on the Word ribbon

Custom HTML-based UI

Add-ins can embed custom HTML-based UI within Office clients. The containers that are available to display the UI vary based on the type of add-in. For example, task pane add-ins display custom HTML-based UI in the right pane of the document; content add-ins display the custom UI directly within Office documents.

Regardless of the type of add-in you create, you can use common building blocks to create custom HTML-based UI. We recommend that you use Office UI Fabric for these UI elements so that your add-in integrates with the Office look and feel. You are also welcome to use your own UI elements to express your own brand.

Office UI Fabric provides the following UI elements:

  • Typography
  • Color
  • Icons
  • Animations
  • Input components
  • Layouts
  • Navigation elements

You can download Office UI Fabric from Github.

For a sample that shows how to use Office UI Fabric in add-ins, see Office Add-in Fabric UI Sample.


If you decide to use your own set of fonts and icons, make sure they don't conflict with those of Office. For example, don't use icons that are the same as or similar to those in Office, but represent something different in your add-in.

Creating a customized color palette

If you decide to use your own color palette, keep the following in mind:

  • Use color to help communicate your brand value to users, and to add emotion and delight to your add-in user experience.
  • Use color meaningfully and consistently in your add-in. For example, choose one color as an accent to give your add-in a consistent visual theme.
  • Avoid using the same color for both interactive and non-interactive elements. If you use color to indicate items users can interact with, such as navigation, links, and buttons, don't use the same color for static items.
  • If you use color for text or white text on a colored background, be sure that your colors have enough contrast to meet accessibility guidelines (4.5:1 contrast ratio).
  • Be aware of color blindness —- use more than just colors to indicate interactivity.


Whether you decide to adopt the Office color scheme or to use your own, we encourage you to use our Theming APIs. Add-ins that are part of the Office theming experience will feel much more integrated with Office.

See also