The .i3d file format is an method of storing the Inspect3D application's workspace settings as XML, ensuring that they are both human- and machine-readable. Inspect3D allows users to save its current workspace settings from the Save Workspace As or Save Workspace toolbar items. Previously-saved application workspace settings can be loaded and applied from the Load Workspace toolbar item.

As an XML document, an .i3d file is made up of hierarchical elements that are demarcated by tags, indicated by the < and > characters. An element consists of a start tag, <elementname>, and end tag, </elementname>, and all of the characters in between. Alternatively, an element can be defined by a single tag, <elementname />.

Tags can also contain attributes in the name=“value” format, further describing the associated element.

1. The top-level element in an .i3d file is workspace. It contains a number of subordinate elements.

2. An .i3d file contains a number of different second-level elements. These include:

1. Library: File path to the currently loaded CMO library
2. class_style: Styles applied to classes of signals
3. ex_style: Styles applied to excluded signals
4. vert_style: Styles applied to vertical lines
5. PCA_Data: Settings for principal component analysis
6. PCA_Prefs: Preferences for the 6 PCA result sub-windows
7. query_info: Definitions for currently applied queries
8. vert_style: Styles applied to vertical lines
9. graph_para: Settings for the 6 PCA result sub-windows
10. orig_pref: Settings for the Queried Data window
11. Intermediate_Events: Styles applied to any defined Intermediate Events
12. I3D_Info: Version information for the Inspect3D application