docs/api/sql/Measurement-Functions/ST_Perimeter.md

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# ST_Perimeter

Introduction: This function calculates the 2D perimeter of a given geometry. It supports Polygon, MultiPolygon, and GeometryCollection geometries (as long as the GeometryCollection contains polygonal geometries). For other types, it returns 0. To measure lines, use [ST_Length](ST_Length.md).

To get the perimeter in meters, set `use_spheroid` to `true`. This calculates the geodesic perimeter using the WGS84 spheroid. When using `use_spheroid`, the `lenient` parameter defaults to true, assuming the geometry uses EPSG:4326. To throw an exception instead, set `lenient` to `false`.

![ST_Perimeter](../../../image/ST_Perimeter/ST_Perimeter.svg "ST_Perimeter")

Format:

`ST_Perimeter(geom: Geometry)`

`ST_Perimeter(geom: Geometry, use_spheroid: Boolean)`

`ST_Perimeter(geom: Geometry, use_spheroid: Boolean, lenient: Boolean = True)`

Return type: `Double`

Since: `v1.7.0`

SQL Example:

```sql
SELECT ST_Perimeter(
        ST_GeomFromText('POLYGON((0 0, 0 5, 5 5, 5 0, 0 0))')
)
```

Output:

```
20.0
```

SQL Example:

```sql
SELECT ST_Perimeter(
        ST_GeomFromText('POLYGON((0 0, 0 5, 5 5, 5 0, 0 0))', 4326),
        true, false
)
```

Output:

```
2216860.5497177234
```