# startSize3D

> The initial 3D size of the particle. The current size of the particle is calculated procedurally based on this value and the active size modules.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.5/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

```csharp
public Vector3 startSize3D { get; set; }
```

### Remarks

This is particle's size in meters in world space.