# Merging box colliders for optimization

Look at the picture.

The figure on the left shows the individual box colliders in green.

The yellow boxes on the right are the results of the optimization of the original box colliders.

What is the algorithm that makes this possible?

Assuming you have a list of BoxCollider that need to be combined, you can access each of their bounds properties, which consist of the boxes' center and extents. With this two information in mind, you can easily calculate the minimum and maximum x, y, and z coordinates of the boxes.
The combined BoxCollider will have these two corners: and . From upper and lower corners, you can calculate the center and extents of the combined BoxCollider.
All you need to do later is remove or disable initial BoxColliders in your list.