Constraint Length

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This page is a translated version of the page Sketcher ConstrainDistance and the translation is 0% complete.
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Constraint Length.svg Constraint Length

Sketch → Sketcher constraints → Constrain distance
Standard genväg
Shift + D
Introducerad i version
Se även
Constraint HorizontalDistance, Constraint VerticalDistance


Constrain distance defines the length of a line, the perpendicular distance between a point and a line, the distance between two points, or, introduced in version 0.21, the distance between the edges of two circles or between the edge of a circle and a line.

Sketcher ConstrainDistance example.png


  1. Pick one line, or one point and one line, or two points, or the edges of two circles, or the edge of one circle and one line.
  2. There are several ways to invoke the command:
    • Press the Sketcher ConstrainDistance.svg Constrain distance button in the Sketcher toolbar.
    • Use the K then D keyboard shortcut.
    • Use the Sketch → Sketcher constraints → Sketcher ConstrainDistance.svg Constrain distance entry from the top menu.
  3. A pop up dialog opens to edit or confirm the value. Press OK to validate.

Note: the constraint tool can also be started with no prior selection (apart from circle to circle and circle to line cases). To set the perpendicular distance between a point and a line, the point needs to be selected first. By default the command will be in continue mode to create new constraints; press the right mouse button or Esc once to quit the command.


If applicable please consider using the Sketcher ConstrainDistanceX.svg Horizontal distance or Sketcher ConstrainDistanceY.svg Vertical distance constraints instead. These constraints are more robust and faster to calculate than the ConstrainDistance tool.


Distance from origin:

Sketch.addConstraint(Sketcher.Constraint('Distance', Edge, PointOfEdge, -1, 1, App.Units.Quantity('123.0 mm')))

Distance between two vertices:

Sketch.addConstraint(Sketcher.Constraint('Distance', Edge1, PointOfEdge1, Edge2, PointOfEdge2, App.Units.Quantity('123.0 mm')))

Length of line (the GUI allows selecting the edge itself, but it is just a shorthand for using the two extremities of the same line):

Sketch.addConstraint(Sketcher.Constraint('Distance', Line, 1, Line, 2, App.Units.Quantity('123.0 mm')))

Distance from point (Edge, PointOfEdge) to perpendicular point on line (Line):

Sketch.addConstraint(Sketcher.Constraint('Distance', Edge, PointOfEdge, Line, 0, App.Units.Quantity('123.0 mm')))

Distance between the edges of two circles:

Sketch.addConstraint(Sketcher.Constraint('Distance', Circle1, 0, Circle2, 0, App.Units.Quantity('123.0 mm')))

The Sketcher scripting page explains the values which can be used for Edge, Edge1, Edge2, PointOfEdge, PointOfEdge1, PointOfEdge2, Line, Circle1 and Circle2, and contains further examples on how to create constraints from Python scripts.