How to Switch Units in AutoCAD?

To switch units in AutoCAD effectively, it’s essential to follow a systematic approach. Here’s a step-by-step guide outlining the process for various common scenarios:

Creating a New Drawing with Specific Units

1. Start a New Drawing: Launch AutoCAD and initiate a new drawing file by selecting “New” from the menu.

2. Access the Units Command: Type UNITS in the command line and hit Enter. This action opens the Drawing Units dialog box.

3. Select Desired Units: In the dialog box, choose the appropriate unit type from the options provided (e.g., architectural, decimal, fractional, etc.).

4. Use Insert Options: For certain AutoCAD versions (like AutoCAD 2025), input INSERT or CLASSICINSERT to ensure proper handling of existing drawings.

5. Configure Insertion Settings: In the Insert settings, find your previous drawing and adjust the scaling and rotation settings to insert the drawing at the specified coordinates without any scaling or rotation effect.

Converting Units from Inches to Millimeters

1. Open Dimension Style Manager: Navigate to the Dimension menu, then select “Dimension Style.”

2. Create New Dimension Style: Click on “New” in the Dimension Style Manager.

3. Set Up New Style Parameters: In the New Dimension Style window, give your style a name. Select a base style you wish to start from and ensure it is set for “All Dimensions.”

4. Configure Primary Units: Go to the Primary Units tab. Enter “mm” in the Suffix box and set the scale factor to 25.4, as there are 25.4 millimeters in an inch.

Changing Units from Inches to Centimeters

1. Start the Scaling Process: Open the Modify panel from the Home tab and select “Scale.”

2. Select All Objects: At the prompt asking for objects, type “ALL” to include every element in your drawing.

3. Choose a Base Point: Enter a base point. Typically, the base point is set at (0, 0) for simplicity.

4. Input the Scale Factor: To convert inches to centimeters, input the appropriate scale factor, which is 2.54.

Checking Current Units in AutoCAD

1. Access the Application Menu: Click on the Application menu located at the upper left corner of the AutoCAD window.

2. Select Drawing Utilities: From the drop-down menu, go to “Drawing Utilities.”

3. Open Units Settings: Click on “Units” to display the current unit configuration, or alternatively, type UN in the command line to quick access the units dialog.

Setting Units and Limits for a Drawing

1. Open AutoCAD: Launch the software to start the operation.

2. Access Limits Command: Type LIMITS in the command line and hit Enter.

3. Input Coordinates for Limits: Enter the coordinates for the lower-left corner (e.g., (0, 0)) and press Enter.

4. Specify Upper-Right Coordinates: Next, input the coordinates of the upper-right corner (e.g., (200, 200)) and press Enter again.

5. Finalize with Z Enter: Enter “Z” to complete the setup of drawing limits.

Changing MM Scale in AutoCAD

1. Get Started with a New Drawing: Open AutoCAD Architecture or AutoCAD MEP and create a blank drawing.

2. Open the Units Dialog: Enter UNITS to open the Drawing Setup dialog.

3. Set Unit Type: Choose “Millimeters” or “Meters” from the units options.

4. Set as Default: Check the box that indicates “Save as Default” if you want these settings for future drawings.

Frequently Asked Questions

How do I confirm which unit system is currently active in AutoCAD?
To determine the unit system, go to Application menu > Drawing Utilities > Units, or simply type UN in the command line to view the current settings.

Can I change units after creating a drawing?
Yes, you can adjust units after making a drawing by using the UNITS command to reassign the desired unit configurations for the drawing.

What happens to dimensions when I change units?
When you change the unit system, dimensions may need to be adjusted to stay consistent with the new unit scale. It’s advisable to double-check dimensions after making adjustments.