【Blender】How to Fix Mirror Modifier Not Working Symmetrically

Problem

After applying the Mirror Modifier, the object isn't being duplicated symmetrically (left-right or top-bottom).

Cause: Object Origin Position

The Mirror Modifier creates a mirrored copy around the object's origin (the orange dot).

If the origin is at the center of the object, the mirrored copy overlaps in place, making the mirror effect invisible.

Solution

Move the origin to the world center (0,0,0) or another appropriate point, and the object will mirror correctly around that axis.

Steps

1. Place the 3D Cursor at World Origin

   • Press Shift + C (moves the 3D cursor to position 0,0,0)

2. Make Sure You're in Object Mode

   • If in Edit Mode, press Tab to switch to Object Mode

3. Move Origin to 3D Cursor Position

   • With the object selected, right-click
   • Select Set Origin → Origin to 3D Cursor

The origin will now be at the world center, and the Mirror Modifier will work correctly.

Additional Notes

• Origin: The reference point for an object. Acts as the center for translation, rotation, and scale operations
• 3D Cursor: A tool in Blender used to specify positions
• You can change the mirror axis (X/Y/Z) in the modifier properties as needed