What Is Parametric Modelling in AutoCAD?

Parametric modelling in AutoCAD is a powerful feature that allows you to create and modify 2D and 3D designs by using parameters. These parameters, also known as constraints, define the relationships between different elements in your design. By changing the values of these parameters, you can easily modify your design without having to redraw or recreate it from scratch.

How Does Parametric Modelling Work?

When you create a drawing or a model in AutoCAD, you can apply various constraints to its elements. These constraints define the dimensions, angles, distances, and relationships between different objects. For example, you can specify that two lines are perpendicular or that a circle has a specific radius.

Once you have applied these constraints, the geometry of your design becomes parametrically driven. This means that if you change the value of one parameter, all other related objects will automatically adjust accordingly. For instance, if you increase the radius of a circle, any connected lines or dimensions will update instantaneously.

The Benefits of Parametric Modelling

Parametric modelling offers several benefits for designers and engineers:

  • Flexibility: With parametric modelling, you can easily make changes to your design at any stage of the process without starting from scratch. This flexibility allows for faster iterations and modifications.
  • Accuracy: By defining precise relationships between objects, parametric modelling ensures that your designs maintain accurate proportions and dimensions.
  • Ease of Use: AutoCAD provides an intuitive interface for applying constraints and parameters to your designs. You can easily define relationships using a variety of tools such as geometric constraints and dimensional constraints.
  • Time Savings: With parametric modelling, repetitive tasks like modifying multiple instances of an object become effortless. You only need to change the parameters once, and the entire design updates accordingly.

Common Parametric Modelling Techniques

Here are some commonly used techniques in parametric modelling:

Geometric Constraints:

Geometric constraints are used to define relationships between geometric objects. These constraints include coincident, collinear, parallel, perpendicular, tangent, and more. For example, you can ensure that two lines are always parallel or that a point lies on a circle.

Dimensional Constraints:

Dimensional constraints allow you to control the size and position of objects by setting specific values. You can define lengths, angles, radii, distances, and other dimensions. By modifying these values later on, your design will adjust accordingly.

Equations and Formulas:

In addition to geometric and dimensional constraints, AutoCAD also allows you to use equations and formulas in your parametric designs. You can create relationships based on mathematical expressions or logical conditions. This advanced feature enables complex parametric modelling scenarios.


Parametric modelling in AutoCAD is a powerful tool for creating flexible and accurate designs. By using parameters and constraints, you can easily modify your designs without starting from scratch. This saves time, improves accuracy, and enhances productivity for designers and engineers.

Incorporating parametric modelling techniques into your workflow can greatly improve your efficiency when working with AutoCAD. So why not give it a try? Start exploring the possibilities of parametric modelling today!