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# itemSize

The default size to use for cells.

```
var itemSize: CGSize { get set }
```

## Discussion

If the delegate does not implement the [`collectionView(_:layout:sizeForItemAt:)`](/documentation/UIKit/UICollectionViewDelegateFlowLayout/collectionView(_:layout:sizeForItemAt:)) method, the flow layout uses the value in this property to set the size of each cell. This results in cells that all have the same size.

The default size value is (50.0, 50.0).

---

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