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# activeProcessorCount

The number of active processing cores available on the computer.

```
var activeProcessorCount: Int { get }
```

## Discussion

Whereas the [`processorCount`](/documentation/Foundation/ProcessInfo/processorCount) property reports the number of advertised processing cores, the [`activeProcessorCount`](/documentation/Foundation/ProcessInfo/activeProcessorCount) property reflects the actual number of active processing cores on the system. There are a number of different factors that may cause a core to not be active, including boot arguments, thermal throttling, or a manufacturing defect.

This property value is equal to the result of entering the command `sysctl -n hw.logicalcpu` on the current system.

---

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