Capsule Collider 2D

The Capsule ColliderAn invisible shape that is used to handle physical collisions for an object. A collider doesn’t need to be exactly the same shape as the object’s mesh - a rough approximation is often more efficient and indistinguishable in gameplay. More info
See in Glossary 2D is a Collider that interacts with the 2D physics system. The capsule shape has no vertex corners and has a continuous round circumference. This shape allows the Capsule ColliderA capsule-shaped collider component that handles collisions for GameObjects like barrels and character limbs. More info
See in Glossary 2D to not get easily caught in the corners of other Colliders. The capsule shape is considered solid and not hollow, which means any other Collider 2Ds that are inside the Capsule Collider 2D are considered to be in contact with the Collider and are forced out of it over time.

The settings that define the Capsule Collider 2D are Size and Direction. Both the Size and Direction properties refer to X and Y (horizontal and vertical, respectively) in the local space of the Capsule Collider 2D, and not in world-space.

A typical way to set up the Capsule Collider 2D is to set the Size to match the Direction. For example, if the Capsule Collider 2D’s Direction is Vertical, the Size of X is 0.5 and the Size of Y is 1, this makes the vertical direction capsule taller, rather than wider.

In the example below, the X and Y are represented by the yellow lines.

Capsule configuration examples

You can change the Capsule Collider 2D with different configurations. Below are some examples.

Note that when the X and Y of the Size property are the same, the Capsule Collider 2D always approximates to a circle.

Note: A known issue in the 2D physics system is that when a GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary moves across multiple Colliders, one or several of the Colliders may register a collisionA collision occurs when the physics engine detects that the colliders of two GameObjects make contact or overlap, when at least one has a Rigidbody component and is in motion. More info
See in Glossary between the Colliders. This may occur even when the Colliders are perfectly aligned. This collision can cause the Collider to slow down or stop.

While constructing a surface with the Capsule Collider 2D can help reduce this problem, it is recommeneded to use a single Collider rather than multiple Colliders for a surface, such as the Edge Collider 2D.