Bounds.size

Description

The total size of the box. This is always twice as large as the extents.

size.x is the width, size.y is the height and size.z is the depth of the box.

//This script outputs the size of the Collider bounds to the console

using UnityEngine;

public class Example : MonoBehaviour
{
    Collider m_Collider;
    Vector3 m_Size;

    void Start()
    {
        //Fetch the Collider from the GameObject
        m_Collider = GetComponent<Collider>();

        //Fetch the size of the Collider volume
        m_Size = m_Collider.bounds.size;

        //Output to the console the size of the Collider volume
        Debug.Log("Collider Size : " + m_Size);
    }
}