Mirror is a toggle in Fusion 360's Design workspace, found in the Modify menu

To enable mirror in Fusion 360, open your design in the Design workspace, select the feature or body you want to mirror, then go to the Modify menu and click Mirror. A dialog box appears where you choose the plane of symmetry — XY, YZ, or XZ — and Fusion creates a mirrored copy on the opposite side. The mirrored feature stays linked to the original, so changes to one update the other automatically.

Mirror works on individual features (like a hole or pocket) or on entire solid bodies. If you mirror a feature, Fusion adds it to your design history as a new step. If you mirror a body, you get a separate body that you can keep, delete, or combine with the original using Boolean operations.

The mirror plane you choose depends on how your model is oriented. Most models use the XY plane (horizontal) or YZ plane (vertical), but you can also select a custom plane if your geometry needs it.

Key Takeaways

  • Select the feature or body you want to mirror, then open Modify > Mirror from the top menu.
  • Choose your mirror plane (XY, YZ, or XZ) in the dialog that appears, then click OK.
  • Mirrored features stay linked to the original, so editing one automatically updates the other.
  • You can mirror individual features within a body or mirror an entire body as a separate object.

Mirroring a single feature step by step

Start in the Design workspace with your model open. In the browser panel on the left, expand the body that contains the feature you want to mirror. Click on the feature itself — for example, a pocket, hole, or fillet — to select it. The feature highlights in the 3D view.

Go to the Modify menu at the top of the screen and click Mirror. A dialog box opens showing your feature name and asking you to select a mirror plane. Click on the plane you want to use: XY, YZ, or XZ. Most of the time, XY (the horizontal plane) or YZ (the vertical plane) is what you need. Once you choose, click OK. Fusion adds the mirrored feature to your design history, and you see the copy appear in the 3D view on the opposite side of the plane.

If the mirror appears on the wrong side or in the wrong direction, undo the operation (Ctrl+Z or Cmd+Z), select the feature again, and choose a different plane.

Mirroring an entire body

If you want to mirror a whole body instead of a single feature, the process is similar but the result is different. In the browser, right-click on the body you want to mirror and select Mirror Body from the context menu. Alternatively, select the body in the 3D view, go to Modify > Mirror, and proceed as you would with a feature.

When you mirror a body, Fusion creates a new, separate body. This new body is not linked to the original the way a mirrored feature is. You can move it, delete it, or combine it with the original body using Boolean operations like Union or Intersect. This approach is useful when you want to create symmetrical parts that you might later join into one solid.

Understanding mirror planes and how to choose the right one

Fusion 360 uses three standard mirror planes: XY, YZ, and XZ. These correspond to the three axes of your coordinate system. The XY plane is horizontal (perpendicular to the Z axis), the YZ plane is vertical (perpendicular to the X axis), and the XZ plane is also vertical (perpendicular to the Y axis).

To pick the right plane, think about which direction you want the mirror to happen. If you have a hole on the left side of your part and you want it mirrored to the right side, you use the YZ plane. If you have a feature on the top and want it on the bottom, you use the XY plane. If your model is oriented differently than you expect, rotate the view to see the axes — they appear as colored lines in the corner of the 3D view (red for X, green for Y, blue for Z).

If none of the standard planes work for your geometry, you can create a custom mirror plane. In the Modify menu, look for the option to select a custom plane, then click on a plane in your design or create one using the Construct menu.

Editing and breaking the link between mirrored features

When you mirror a feature, the two versions stay linked. If you edit the original feature — say, you change the hole diameter — the mirrored copy updates automatically. This is useful for keeping symmetrical parts consistent, but sometimes you want to break that link and edit one side independently.

To break the mirror link, right-click on the mirrored feature in the browser and select Break Link. The mirrored feature becomes independent and no longer updates when you change the original. You can then edit it separately without affecting the other side.

If you want to delete the mirrored feature entirely, right-click it in the browser and select Delete. This removes only the mirror, not the original feature.

Common reasons mirror doesn't work as expected

If you try to mirror a feature and nothing happens, or the mirror appears in the wrong place, check these things first. Make sure you have actually selected the feature — it should highlight in the browser and in the 3D view. If you selected a body instead of a feature, the Mirror command behaves differently. Also check that the feature you are trying to mirror is not dependent on other features that do not exist on the opposite side of the plane. For example, if a hole is based on a sketch that only exists on one side, mirroring may fail.

Another common issue is choosing the wrong mirror plane. If the mirror appears upside down or backwards, undo and try a different plane. You can also rotate your view to see the axes more clearly and understand which plane will give you the result you want.

If Fusion shows an error message, read it carefully — it usually tells you what is preventing the mirror. Common blockers include selecting a feature that cannot be mirrored (like a body operation) or trying to mirror across a plane that does not intersect your geometry.

When to use mirror versus creating geometry manually

Mirror is fast when you have a symmetrical design and you want to avoid drawing the same feature twice. It is especially useful early in your design when you know both sides will be identical. However, if your two sides are similar but not exactly the same — for example, slightly different hole sizes or different fillet radii — you may be better off creating each side separately so you can edit them independently.

Mirror also works well for parts that are truly symmetrical, like brackets, enclosures, or mechanical components. For organic shapes or parts with subtle asymmetry, you might find it easier to model the whole thing without mirror and adjust as you go.

Frequently Asked Questions

Can I mirror a feature that is based on a sketch?

Yes, but the sketch itself does not mirror. Fusion mirrors the feature (the hole, pocket, or extrusion) that the sketch created. If you want the sketch to exist on both sides, you need to create or mirror the sketch separately using the Sketch menu.

What happens if I mirror a feature and then edit the original?

The mirrored copy updates automatically to match the original. If you want to edit one side without changing the other, right-click the mirrored feature and select Break Link first.

Can I mirror across a custom plane instead of XY, YZ, or XZ?

Yes. In the Mirror dialog, instead of selecting a standard plane, click on a custom plane in your design, or create one using the Construct menu. This is useful for parts that are oriented at an angle.

How do I undo a mirror if I made a mistake?

Press Ctrl+Z (Windows) or Cmd+Z (Mac) to undo the mirror operation. The mirrored feature disappears and you return to the state before you ran Mirror. You can then select the feature again and try a different plane.

Is there a difference between mirroring a feature and mirroring a body?

Yes. Mirroring a feature keeps the two versions linked within the same body, so they update together. Mirroring a body creates a separate, independent body that you can move or combine with the original using Boolean operations.