# Sketch Constraints

Apply geometric relationships such as tangency and perpendicularity to sketch curves.

As you create geometry, many sketch constraints are automatically applied. For instance, if you draw a line that is nearly horizontal, a horizontal constraint will be created on that line automatically, making it precisely horizontal for you. When you modify a sketch, the constraints ensure that the intended relationships between the sketch entities remain intact.

## Apply or Remove Sketch Constraints

Apply sketch constraints to geometry to ensure that the intended relationships between sketch entities remain intact, or remove sketch constraints to allow more freedom to create free-form objects.

Constraint | Description |
---|---|

Fixed |
Lock the position of any sketch curve. When a line is fixed, you can still move the end points to change the length. The end points of a line are separate entities and can be fixed independently. Note: To delete all fixed constraints,
right-click on the constraint and select
Remove Fix. |

Horizontal |
Lines are constrained to be horizontal. You can also use this contraint to align points. |

Vertical |
Lines are constrained to be vertical. You can also use this contraint to align points. |

Midpoint |
A point is constrained to be the midpoint of a curve. |

Coincident |
A point is constrained to be coincident with another
sketch entity. Tip: When
you hover over coincident sketch entities, a badge
appears next to the cursor and a tooltip appears. This indicates that you can hold down the left mouse button to access the coincident picking menu, from which you can select the desired sketch entity. |

Collinear |
Lines are constrained to lie along the same straight line. |

Parallel |
Lines are constrained to be parallel. |

Perpendicular |
Lines are constrained to be perpendicular. |

Tangent |
A line is constrained to be tangent to an arc, or an arc is constrained to be tangent to another arc. |

Concentric |
Arcs or circles are constrained to have the same center. |

Equal |
Lines are constrained to have the same length. Arcs and circles are constrained to have the same radius. |

Offset |
A sketch curve is offset from another sketch curve. Note: This constraint cannot be applied
from the sketch constraint context menu. |

Symmetric |
Two curves are constrained to be symmetric about a construction line (e.g., mirrored curves). |

Tan/Tan | When you sketch a line between two circles, the Tan/Tan inference helps you make the line tangent to both circles. |

Perp/Perp | When you sketch a line between two circles, the Perp/Perp inference helps you make the line perpendicular to both circles. |

Select Other | This is not a constraint. Select this option when selecting overlapping sketch entities to specify which sketch entity you wish to select. |

- To hide all constraints, deselect Show constraints under Sketching in .
- If your horizontal constaints appear vertical and vice versa, use the Align Axes option in the context menu to align the sketch axes so that the x-axis is horizontal and the y-axis is vertical.
- Select Delete All Constraints from the context menu to remove all constraints from all sketches in the model.
- Select Remove Fix from the context menu to remove all fixed constraints in the model.