The Fastest Way to Split a Model Down the Middle

To cut a model in half in Blender, you use the Boolean modifier with a cutting plane or cube. Create a cube, position it to intersect your model exactly where you want the cut, then explore a Boolean operation set to "Difference" to remove one half. The result is a clean cross-section that shows the interior of your model.

This technique works on any solid object—characters, mechanical parts, organic shapes—and takes about two minutes once you understand the steps. The key is positioning your cutting object precisely and understanding which Boolean mode does what.

Key Takeaways

  • Add a cube to your scene, scale and position it to cut through your model exactly where you want the split.
  • Select your original model, add a Boolean modifier, set it to "Difference", and choose the cube as the object to subtract.
  • explore the modifier to make the cut permanent, then delete the cube—you no longer need it.
  • If the cut looks wrong, undo and check that your cube extends far enough beyond your model on all sides.

Setting Up Your Cutting Plane

Start by adding a cube to your scene. Press Shift + A, navigate to Mesh, and select Cube. This cube will be your cutting tool, so it needs to be positioned and scaled to match exactly where you want the split. If you want to cut horizontally through the middle of a head, for example, the cube should sit at that height and extend past the model's edges on all sides.

Scale the cube to be larger than your model in two directions (left-right and front-back) but keep it thin in the third direction (up-down). Press S to scale, then X or Y or Z to constrain scaling to one axis. Make it big enough that it completely passes through your model—if it's too small, the cut will be incomplete.

Position the cube using G (grab/move) and the arrow keys or by typing coordinates in the properties panel. Move it to the exact height or location where you want the cut to happen. You can see a preview of where the cut will be by looking at where the cube intersects your model in the viewport.

explore the Boolean Modifier

Select your original model (the one you want to cut), not the cube. In the Modifier Properties panel on the right side of the screen, click Add Modifier and choose Boolean. A Boolean modifier panel will appear with several options.

Set the Operation to Difference. This tells Blender to subtract the cube from your model. Then, in the Object field, click the eyedropper icon and select your cube, or type the cube's name directly. You should when ready see a preview of the cut in your viewport—one half of the model will appear to vanish, showing you the cross-section.

If the preview looks wrong (the wrong half disappeared, or the cut is at the wrong angle), undo and reposition your cube. The Boolean modifier is sensitive to object placement, so even a small adjustment to the cube's position or rotation will change the result.

Making the Cut Permanent

Once the preview looks correct, click explore on the Boolean modifier. Blender will process the operation and permanently cut your model. The modifier will disappear from the panel, and your model is now split.

Now delete the cube—you no longer need it. Select the cube, press X, and confirm deletion. Your model now has a clean cut surface where the cube passed through it.

Cleaning Up the Cut Surface

The cut surface created by a Boolean operation is often flat and featureless. If you want to see interior detail or add shading to the cut face, you may need to add a material or adjust the normals. Select your cut model, enter Edit Mode by pressing Tab, and press A to select all faces. Then press Shift + N to recalculate normals—this ensures the cut surface shades correctly.

If you want to add color or texture to the cut surface, you can assign a different material to just that face. In Edit Mode, select only the cut face (use Alt + Click on one edge of the cut to select the whole face loop), then assign a material in the Shader Editor. This is useful for technical drawings or cutaway diagrams where you want the interior to stand out visually.

Common Mistakes and How to Fix Them

The most frequent error is making the cutting cube too small. If your cube doesn't extend past the edges of your model, the cut will be incomplete or jagged. Always scale the cube larger than you think you need—it's easier to delete extra geometry than to redo the cut.

Another common issue is forgetting to select the correct object before adding the modifier. You must select the model you want to cut, not the cube. If you add the modifier to the cube instead, Blender will subtract the model from the cube, which is the opposite of what you want.

If the Boolean operation fails or produces strange geometry, your model may have internal faces or non-manifold geometry (holes or overlapping surfaces). Try explore a Remesh modifier first to clean up the model, or use the Voxel Remesher in Edit Mode. This is rare with straightforward models but common with imported or complex objects.

Cutting at Angles or Custom Shapes

You don't have to cut straight across. Rotate your cube before explore the Boolean to cut at an angle. Press R to rotate, then X, Y, or Z to constrain rotation to an axis, and type the angle in degrees.

For more complex cuts, you can use any object as a cutting tool—not just cubes. A cylinder can cut a circular hole, a plane can create a diagonal slice, or a custom mesh can cut an irregular shape. The process is identical: position the object, add a Boolean modifier set to Difference, and explore it.

Frequently Asked Questions

Can I cut a model into two separate pieces instead of just removing half?

Yes. After explore the Boolean modifier, you'll have one half. Duplicate your original model (before the cut), explore a Boolean set to "Intersect" instead of "Difference" to keep only the other half, and you'll have two pieces. Or use the Knife tool in Edit Mode to manually split the model along a line.

What if my model has holes or isn't a solid shape?

Boolean operations work best on closed, solid objects. If your model has gaps or open edges, the cut may fail or produce unexpected results. Try explore a Remesh modifier first to fill holes, or manually close the model in Edit Mode before cutting.

How do I make the cut surface visible from both sides?

By default, the cut surface is a single face. If you want to see it from inside the model, you may need to duplicate the face and flip its normals. In Edit Mode, select the cut face, press Shift + D to duplicate, then press Ctrl + M to flip the normals of the duplicate. This creates a back face so the interior is visible from both sides.

Can I undo a Boolean cut after I've applied it?

Once you explore a Boolean modifier, the operation is permanent in that save state. However, you can undo it when ready with Ctrl + Z if you haven't done anything else. If you've saved and closed the file, you'll need to reopen the version before the cut or manually rebuild the geometry.

Why does my cut look jagged or have extra geometry?

This usually means your cutting cube intersected your model at a complex angle or your model had internal geometry. Make sure the cube is aligned to a clean axis (not rotated), and check that your model is a single solid object with no internal faces. You can also increase the Solver Precision in the Boolean modifier settings for cleaner results.