# Sandbox.SandboxSystemExtensions.IsValidTag

```csharp
static bool IsValidTag(string source)
```

Is this string a valid Tag. This is a way to check if a string is a valid tag, project wide. So our logic is always the same.

- not null
- between 1 and 32 chars
- a-z

### Parameters

- `source` (`string`)

### Returns

`bool`

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