The .q3d file format is an method of storing query definitions as XML, ensuring that they are both human- and machine-readable. Inspect3D allows users to save query definitions from the Group Definition dialog. Previously-saved query definitions can be loaded and applied to the CMO library to populate groups in the Group Definition dialog or from the Group Definitions drop-down menu's Load Group Def & Compute Groups option.

As an XML document, a .q3d 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 a .q3d file is queries. It contains an arbitrary (1-n) number of query elements.

2. The second-level element in a .q3d file is query. A query element has a name attribute (the corresponding group's name) and contains an arbitrary (1-n) number of Definition elements.

3. The bottom-level element in a .q3d file is Definition. A Definition element consists of a single tag and encodes a single sub-group via a number of attributes.

Formally, a .q3d file respects the Document Type Definition (DTD):

<!DOCTYPE queries [
  <!ELEMENT queries query+>
  <!ENTITY query Definition+>
  <!ATTLIST query
    name CDATA #REQUIRED
  >
  <!ENTITY Definition>
  <!ATTLIST Definition
    condition CDATA #REQUIRED
    query CDATA #REQUIRED
    workspace CDATA #REQUIRED
    type CDATA #REQUIRED
    folder CDATA #REQUIRED
    name CDATA #REQUIRED
    component CDATA #REQUIRED
    max_elements CDATA #REQUIRED
    negate_result CDATA #REQUIRED
    events CDATA #REQUIRED
    exclude_events CDATA #REQUIRED
    has_tag_ref CDATA #REQUIRED
    tag_logic CDATA #REQUIRED
    tag CDATA #REQUIRED
    has_subject_ref CDATA #REQUIRED
    subject CDATA #REQUIRED
    normalize_info CDATA #REQUIRED
  >
]>