Property editor

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The property editor appears when the Model tab of the combo view is active; it allows managing the publicly exposed properties of the objects in the document.

Generally, the property editor is intended to deal with just one object at one time. The values shown in the property editor belong to the active object of the active document. Despite this, some properties like colors, can be set for multiple selected objects. If there are no elements selected, the property editor will be empty.

Not all properties can be modified always; depending on the specific status of the property, some of them will be invisible (not listed), or be read-only (not editable).

FreeCAD Property editor empty.png

Empty property editor, when no object is selected.

Property types

A property is a piece of information like a number or a text string that is attached to a FreeCAD document or an object in the document.

Custom scripted objects can use any of the property types defined in the base system. See the full list in Property.

Some of the most commonly used property types are:


Different objects may have different types of properties. However, many objects have the same types because they are derived from the same internal class. For example, most objects that describe geometrical shapes (lines, circles, rectangles, solid bodies, imported parts, etc.), have the "Placement" property that defines their position in the 3D view.

View and Data properties

There are two classes of feature properties accessible through tabs in the property editor:

  • View properties, related to the "visual" appearance of the object. The View properties are tied to the ViewProvider (ViewObject attribute) of the object, and are only accessible when the graphical user interface (GUI) is loaded. They are not accessible when using FreeCAD in console mode, or as a headless library.
  • Data properties, related to the "physical" parameters of the object. The Data properties define the essential characteristics of the object; they exist at all times, even when FreeCAD is used in console mode, or as a library. This means that if you load a document in console mode, you can edit the radius of a circle or the length of a line, even if you cannot see the result on the screen.

For this reason, Data properties are considered to be more "real", as they truly define the geometry of a shape. On the other hand, View properties are less important because they only affect the appearance of the geometry. For example, a circle of 10 mm radius is different from a circle of 5 mm radius; the color of the circle (view property) doesn't affect its shape, but the radius does (data property). In many instances in this documentation, the word "property" is understood to refer to a "Data property".

Basic properties

The most basic scripted object won't show any Data property in the property editor, except for its Label attribute. The Label is a user editable string that identifies the object in the tree view. On the other hand, the Name attribute of an object is assigned at the moment of its creation and cannot be changed; this attribute is read-only, and is not displayed in the property editor either.

A basic parametric object is created as follow

obj = App.ActiveDocument.addObject("App::FeaturePython")
obj.Label = "Plain_object"

FreeCAD Property editor View basic.png FreeCAD Property editor Data basic.png

View and Data tabs of the property editor, for a basic "App::FeaturePython" scripted object.

Most geometrical objects that can be created and displayed in the 3D view are derived from a Part::Feature. See Part Feature for the most basic properties that these objects have.

For 2D geometry, most objects are derived from Part::Part2DObject (itself derived from Part::Feature) which is the base of Sketches, and most Draft elements. See Part Part2DObject for the most basic properties that these objects have.


Actions in the property view were implemented in 0.19.

Right clicking in an empty space of the view, or with a property selected, shows only one command:

  • Show all: if active, in addition to the standard properties that appear already, it shows all the hidden Data and View properties in their respective tabs.
    • Data: "Proxy", "Label2", "Expression Engine", and "Visibility".
    • View: "Proxy".

When the Show all option is active, and one property is selected, more actions are available with a second right click:

  • Show all: deactivates the Show all command, hiding the additional Data and View properties.
  • Add Property: adds a dynamic property to the object; this works with both C++ and Python scripted objects.
  • Expression: brings up the formula editor, which allows using expressions in the property value.
  • Hidden: if active, sets the property as hidden, meaning that it will only be displayed if Show all is active.
  • Output: if active, sets the property as output.
  • NoRecompute: if active, sets the property as not recomputed when the document is recomputed; this is useful when a property should be kept unaffected by other updates.
  • ReadOnly: if active, sets the property to be read-only; it won't be editable any more until this switch is turned off.
  • Transient: if active, sets the property as transient.
  • Touched: if active, it becomes touched, and ready for recompute.
  • EvalOnRestore: if active, it is evaluated when the document is restored.

Example of the properties of a PartDesign object


FreeCAD Property editor View.png


  • ViewBounding Box: Indicates if a box showing the overall extent of the object is to be displayed. Value False, or True (Default, False).
  • ViewControl Point: Indicates if the feature control points are to be displayed. Value False, or True (Default, False).
  • ViewDeviation: Sets the accuracy of the polygonal representation of the model in the 3d view (tessellation). Lower values = better quality. The value is in percent of object's size (deviation in mm = (w+h+d)/3*valueInPercent/100, where w,h,d are the bounding box dimensions).
  • ViewDisplay Mode: Display mode of the feature, Flat lines, Shaded, Wireframe, Points Vue DisplayModePartDesign fr 00.png. (Default, Flat lines).
  • ViewLighting: Lighting One side, Two side Vue Lighting fr 00.png. (Default, Two side).
  • ViewLine Color: Gives the color of the line (edges) (Default, 25, 25, 25).
  • ViewLine Width: Gives the thickness of the line (edges) (Default, 2).
  • ViewPoint Color: Gives the color of the points (ends of the feature) (Default, 25, 25, 25).
  • ViewPoint Size: Gives the size of the points (Default, 2).
  • ViewSelectable: Allows selection of the feature. Value False, ou True (Default, True).
  • ViewShape Color: Give the color shape (default, 204, 204, 204).
  • ViewTransparency: Sets the degree of transparency in the feature of 0 to 100 (Default, 0).
  • ViewVisibility: Determines the visibility of the feature (like the bar SPACE). Value False, or True (Default, True).


FreeCAD Property editor Data.png


  • DataPlacement:

Summary of the data below. Every feature has a placement that can be controlled through the Data Properties table. It controls the placement of the part with respect to the coordinate system. NOTE: The placement properties do not affect the physical dimensions of the feature, but merely its position in space!
If you select the title Placement Options Placement, a button with three small points appears to the right. Clicking this button ..., opens the Tasks_Placement options window.

  • DataAngle:

Specifies the angle to be used with the axis property (below). An angle is set here, and the axis that the angle acts upon is set with the axis property. The feature is rotated by the specified angle, about the specified axis. A usage example might be if you created a revolution feature as required, but then needed to rotate the whole feature by some amount, in order to allow it to line-up with another pre-existing feature.

  • DataAxis:

This property specifies the axis/axes about which the feature is to be rotated. The exact value of rotation comes from the angle property (above). This property takes three arguments, which are passed as numbers in the x, y, and z boxes in the tool. Setting a value for more than one of the axes will cause the part to be rotated in each axis, by the angle value multiplied by the value for the axis. For example, with an angle of 15° set, specifying a value of 1.0 for x, and 2.0 for y will cause the finished part to be rotated 15° in the x-axis AND 30° in the y-axis.

  • DataPosition:

This property specifies the base point to which all dimensions refer. This takes three arguments, which are passed as numbers to the x, y, and z boxes in the tool. Setting a value for more than one of the boxes will cause the part to be translated by the number of units along the corresponding axis.

  • DataLabel:

The Label is the name given to the object (feature), this name can be changed as desired.