---
title: toBoundingRegion()
framework: mapkitjs
role: symbol
role_heading: Instance Method
path: mapkitjs/coordinateregion/toboundingregion
---

# toBoundingRegion()

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

## Declaration

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

## Return Value

Return Value A BoundingRegion.

## Discussion

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: // 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();

## See Also

### Comparing, copying, and converting regions

- [copy()](mapkitjs/coordinateregion/copy.md)
- [equals(anotherRegion)](mapkitjs/coordinateregion/equals.md)
- [toMapRect()](mapkitjs/coordinateregion/tomaprect.md)