# Sandbox.SandboxSystemExtensions.FastHash64

```csharp
static ulong FastHash64(string str)
```

Generate a 64-bit xxhash3 hash from given string.

### Parameters

- `str` (`string`)

### Returns

`ulong`

Declared in [Sandbox.SandboxSystemExtensions](/api/Sandbox.SandboxSystemExtensions).
Assembly: `Sandbox.System`.