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  "title" : "toBoundingRegion()"
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# toBoundingRegion()

Returns the bounding region that corresponds to the specified coordinate region.

```
toBoundingRegion(): BoundingRegion;
```

## Return Value

A [`BoundingRegion`](/documentation/MapKitJS/BoundingRegion).

## Discussion

A bounding region is similar to a coordinate region; both represent a rectangular area on the 2D projected surface of the map. MapKit JS defines a coordinate region by a center coordinate and a span. The framework defines a bounding region by coordinates representing the rectangle’s northeast and southwest corners.

The following example shows how to convert a coordinate region to a bounding region:

```javascript
// Create a coordinate region named myRegion.
const coordinate = new mapkit.Coordinate(37.415, -122.048333);
// The initializer requires parameters in the order of latitude, longitude.
const span = new mapkit.CoordinateSpan(.016, .016);
// The initializer requires parameters in the order of latitude delta, longitude delta.
const myRegion = new mapkit.CoordinateRegion(coordinate, span);

// Convert this coordinate region to a bounding region.
const myBoundingRegion = myRegion.toBoundingRegion();
```

---

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