> ## Documentation Index
> Fetch the complete documentation index at: https://docs.wherobots.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ST_Simplify

This function simplifies the input geometry by applying the Douglas-Peucker algorithm.

<img src="https://mintcdn.com/wherobots/wLm_IRUSNlHZTHJP/images/sql-functions/ST_Simplify/ST_Simplify.svg?fit=max&auto=format&n=wLm_IRUSNlHZTHJP&q=85&s=46015f7cdef4e18cf113fe83b065ece1" alt="ST_Simplify" width="500" height="300" data-path="images/sql-functions/ST_Simplify/ST_Simplify.svg" />

<Note>
  The simplification may not preserve topology, potentially producing invalid geometries. Use [ST\_SimplifyPreserveTopology](/reference/wherobots-db/geometry-data/processing/ST_SimplifyPreserveTopology) to retain valid topology after simplification.
</Note>

## Signatures

```sql theme={"system"}
ST_Simplify(geom: Geometry, tolerance: Double)
```

## Parameters

<ParamField body="geom" type="Geometry" required>
  The input geometry.
</ParamField>

<ParamField body="tolerance" type="Double" required>
  The distance tolerance.
</ParamField>

## Return type

<ResponseField type="Geometry">
  The resulting geometry.
</ResponseField>

## Example

```sql theme={"system"}
SELECT ST_Simplify(ST_Buffer(ST_GeomFromWKT('POINT (0 2)'), 10), 1)
```

```
POLYGON ((10 2, 7.0710678118654755 -5.071067811865475, 0.0000000000000006 -8, -7.071067811865475 -5.0710678118654755, -10 1.9999999999999987, -7.071067811865477 9.071067811865476, -0.0000000000000018 12, 7.071067811865474 9.071067811865477, 10 2))
```