Adding intelligence to your drawings is key to saving time and letting AutoCAD do the cumbersome work for you. In AutoCAD, fields effectively add intelligence to the drawing and help in automating those tasks that can be prone to error, especially when the drawing is changed and recalculation is required. Fields are text objects that are designed to hold information that updates in a drawing when the base information changes, and they can be used in a variety of ways. For example, fields can contain information such as Date, Filename, Sheet Number, or Login name, and they can be used in standard multiline text objects and in attributes and tables. In this blog post, I will show you how to use fields to display the area of a region and how easily it updates the area when the geometry is changed.
Any property of an AutoCAD object can be used as a field. In the figure shown below, the fields display the area of several boundary polylines.
A field can be included into a drawing from the Field dialog box, which can be accessed by clicking 
(Field) in the ribbon’s Insert tab>Data panel.
The following are the steps for adding multiline text with fields that display the area of a polyline:
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Start the Multiline Text command and pick points for the text editor where you want to display the field information.
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In the ribbon, in the Text Editor contextual tab>Insert panel, click
(Field).
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This opens the Field dialog box. Set the Field category to Objects and in the Field names list, select Object.
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In the Object type area, click
(Select object) and select the magenta polyline around the lot in which you are placing the text.
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In the Field dialog box, note that in the Object type area, Polyline is displayed as you selected the magenta polyline geometry. Set the Property to Area, then set the Format and Precision to determine how the area is displayed.
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Close the Field dialog box and note how the area of the polyline is automatically calculated and displayed in the text editor.
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Use grips to stretch one of the boundary polylines to make it larger.
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Regen the drawing to update the field. Note that the area value automatically updates to reflect the changes made to the polyline.
I hope you will explore using fields to automate other tasks, such as title block information and attributes in tables. A detailed explanation, along with a few hands-on practices, has been provided in our AutoCAD 2025 Advanced learning guide.
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