1. Collider.bounds is a world-space AABB
Unity defines Collider.bounds as the world-space bounding volume. Bounds itself is axis-aligned, so a rotated object can have a larger bounding box than the visible collider shape.
2. center and size are not local collider values
bounds.center and bounds.size describe the enclosing world-space box. Do not use them as if they were the original BoxCollider center or size in local coordinates.
3. Disabled or inactive means empty
Unity’s current API notes that Collider.bounds is empty when the collider is disabled or the GameObject is inactive. If values suddenly become zero, check state before assuming data is corrupted.
4. Use min/max for broad tests, not exact contact
Bounds.min, Bounds.max and Bounds.Intersects are useful for rough spatial tests. Exact collision or contact logic should use physics queries, collision callbacks or Collider.ClosestPoint where appropriate.
Official Unity references
Based on current Unity 6 Collider, Collider.bounds and MeshCollider documentation plus Unity trigger-collider setup guidance. Project settings and later engine updates can change behaviour.
Related Unity collider answers
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