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title: ST_Envelope
description: Returns the bounding box (envelope) of a geometry or geography as a new geometry.
kernels:
  - returns: geometry
    args: [geometry]
  - returns: geometry
    args: [geography]
---

## Description

Returns the minimum axis-aligned bounding box of a geometry. This is usually a polygon but can be a linestring for perfectly vertical or horizontal input and is a point if the input is also a point. For geography, the return value is still a rectangular polygon geometry that represents the latitude and longitude range of the input. For geographies that span the antimeridian, a multipolygon is returned (one on each side of the antimeridian).

Because of slight numerical inaccuracy of geographical calculations, the bounds are expanded slightly compared to the corresponding geometry envelope.

## Examples

```sql
SELECT ST_Envelope(ST_Point(1.0, 2.0));
```

```sql
SELECT ST_Envelope(ST_GeomFromWKT('LINESTRING(0 0, 3 4)'));
```

```sql
SELECT ST_Envelope(ST_GeogFromWKT('LINESTRING(0 0, 3 4)'));
```

```sql
SELECT ST_Envelope(ST_GeomFromWKT('LINESTRING(170 3, -170 4)'));
```

```sql
SELECT ST_Envelope(ST_GeogPoint(1.0, 2.0));
```

```sql
SELECT ST_Envelope(ST_GeogFromWKT('LINESTRING(0 0, 3 4)'));
```

```sql
SELECT ST_Envelope(ST_GeogFromWKT('LINESTRING(170 3, -170 4)'));
```