# startSpeed

> The initial speed of particles when emitted. When using curves, this value acts as a scale on the curve.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.0/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

> **Warning:**
>
> **Deprecated.** startSpeed property is deprecated. Use main.startSpeed or main.startSpeedMultiplier instead.

```csharp
public float startSpeed { get; set; }
```