Shrink function

Available with Spatial Analyst license.


Shrinks specified zones of a raster by a specified number of cells.

This is a global raster function.


The specified zone values are considered foreground zones, while the remaining zone values are considered background zones. With this tool, cells in the foreground zones are allowed to be replaced by cells in the background zones.

NoData has the same priority as any valid value to invade areas vacated by shrinking selected values. Therefore, if a selected value is adjacent to NoData, it may become NoData after shrinking.





The input raster for which the identified zones are to be shrunk.

It must be of integer type.

Number Of Cells

The number of cells by which to shrink each specified zone.

The value must be integer, and can be 1 or greater.

Zone Values


The list of zones to shrink.

The zone values must be integer, and they can be in any order.

To specify multiple zones, use a space to separate the zone values.

Related topics

In this topic
  1. Overview
  2. Notes
  3. Parameters