How to enable clipping in Blender: Mirror modifier, Clip Start and Clip End, and Alt+B

Search for clipping in Blender and you land on three different settings. One belongs to the Mirror modifier and keeps a symmetrical model closed down the middle. One sets how near and how far the viewport and the camera can see. The third hides everything outside a rectangle you draw. This guide covers all three, with the menu names of the Blender 5.2 manual.

Which clipping do you need?

How to enable clipping on the Mirror modifier

1. Select the mesh and open the Modifiers tab of the Properties editor.
2. Click Add Modifier, then Generate > Mirror. Shift+A with the mouse over that tab opens the same menu.
3. In the modifier panel, check Clipping.

A new Mirror modifier mirrors along X, with Merge on and Clipping off, so that checkbox is usually the missing step. With Clipping on, vertices cannot pass through the mirror plane when you transform them in Edit Mode. Vertices that come within the Merge Distance of their mirror copy snap together on the plane and stay there.

This is what you want when you model half of a character, a car body or a bottle. Move or extrude an edge loop toward the center and it stops at the seam instead of passing through and overlapping its mirror copy. The flip side, from the manual: as long as Clipping is on, vertices on the mirror plane cannot leave it. Turn it off for a moment if you need to pull one away from the center.

The related settings:

• Merge joins a vertex with its mirror copy when they are within Merge Distance, 0.001 m on a new modifier. Without it, the two halves stay separate along the seam.
• Bisect cuts a mesh that already crosses the plane and keeps one side; Flip picks which side.
• Mirror Object uses another object, usually an empty, as the mirror center instead of the mesh's own origin.

Clipping and Merge only help if the mirror plane sits where you expect, and that plane passes through the object origin. To put it exactly on the center edge: in Edit Mode, select that edge, press Shift+S and choose Cursor to Selected, go back to Object Mode, then use Object > Set Origin > Origin to 3D Cursor.

When the model is finished, apply the modifier (Ctrl+A over its panel) or keep it live for later edits. To smooth a mirrored model, the Subdivision Surface guide covers the modifier most often stacked with it.

Clip Start and Clip End in the 3D Viewport

The viewport only draws geometry between two distances from the view. To change them:

1. Hover over the 3D Viewport and press N to open the Sidebar.
2. Open the View tab, View panel.
3. Set Clip Start and Clip End.

Anything closer than Clip Start or farther than Clip End is not shown. The defaults are 0.01 m and 1000 m. In orthographic view, the viewport uses minus Clip End in place of Clip Start.

Why an object gets cut when you zoom in

If part of the model disappears and you can see inside it as you zoom, the view is closer to the surface than Clip Start. It shows up most on small objects: a ring or a watch modeled at real size is only a few centimeters across. Lower Clip Start until the surface stays whole.

If the view instead seems to hit a wall and stops getting closer, that is not clipping. Blender orbits and zooms around a center point. Select the object and use View > Frame Selected (Numpad .), center the view under the mouse with Alt+middle click, or move with Dolly View or Walk/Fly navigation.

Scene scale and depth precision

It is tempting to set a tiny Clip Start and a huge Clip End once and for all. The manual warns against it: a large range reduces depth precision, which causes visible artifacts, and can make operations that depend on the depth buffer unreliable. Its advice is to increase the near clipping on large scenes and to decrease the far clipping when nothing is seen from a distance. Fit the range to the scene: a small Clip Start for jewelry, a larger Clip Start and Clip End for a city block or a landscape.

Camera Clip Start and Clip End

A camera has its own range, separate from the viewport's. Select the camera, open its Object Data tab (the camera properties) and find Clip Start and Clip End in the Lens panel. A camera added with Shift+A starts at 0.1 m and 1000 m.

That range is what counts when you look through the camera with Numpad 0, and in the render. In a large scene, objects that show up in the normal viewport can vanish in camera view: the manual's first suspect is a camera clipping distance that is too low. Raise Clip End until they come back.

• Turn on Show Limits in the camera's Viewport Display panel and the clip range appears as two yellow connected dots along the camera's line of sight.
• An object outside the range is not seen directly by the camera, but light bounces are not clipped, so it still affects the image indirectly.
• The manual notes that limited clip values matter for precision in viewport rendering, while ray-traced renders handle more extreme values.

The Blender camera guide covers the other lens settings.

Clipping Region: isolate part of the view with Alt+B

1. In the 3D Viewport, press Alt+B, or use View > View Regions > Clipping Region.
2. Drag a rectangle with the left mouse button.
3. Orbit the view: only what lies inside the volume is visible.

The rectangle becomes a clipping volume bounded by four planes: a box of infinite length in orthographic view, a pyramid of infinite height in perspective. Selection, painting, sculpting and transform snapping ignore the geometry outside it, which makes it handy for working inside a dense model or on one room of a building. Press Alt+B again to remove it.

Do not confuse it with Ctrl+B, which draws a Render Region, the area that gets rendered, or with Local View (Numpad /), which isolates the selected objects rather than a slice of space.

Common clipping mistakes

• A gap or an overlap at the center of a mirrored model. Clipping or Merge is off. Turn both on.
• The mirrored half appears in the wrong place. The object origin is not on the center line. Move it with Origin to 3D Cursor, or use a Mirror Object.
• Center vertices will not move sideways. Clipping holds them on the mirror plane. Turn it off, move them, turn it back on.
• Vertices near the center do not merge. They are farther from their mirror copy than the Merge Distance. Move them closer, or raise the distance slightly.
• Half the scene is gone, yet nothing is hidden in the Outliner. A clipping region is still active. Press Alt+B.
• Surfaces look broken in the viewport but render fine. The clip range is too wide for the scene. Raise Clip Start or lower Clip End.
• The viewport shows a distant background that the render leaves out. The camera's Clip End is shorter than the viewport's. Check the camera's Lens panel.