It is a single number with the value 0 (the object cannot be resized by the user) or 1 (the object may be resized by the user). The default is 1.

For a Form , HTMLRenderer or SubForm, the Sizeable property may only be set by ⎕WC and cannot subsequently be altered using ⎕WS. An attempt to do so generates a NONCE ERROR. For a Form or HTMLRenderer, the default value is 1 and the object occupies a standard resizeable window with a border. Note that the value of Sizeable is independent of the values of the MaxButton and MinButton properties, so that a Form or HTMLRenderer with MaxButton 1 can be maximised even though its Sizeable property is 0.

For other objects, the default value of the Sizeable property is 0. However, setting it to 1 (which may be done dynamically using ⎕WS) allows the user to resize it with the mouse.

In all these cases, when the user resizes an object, the object will generate a Configure (31) event.

Sizeable also applies to the Locator object. In this case, a value of 1 implies "rubberbanding" and a value of 0 means "no rubberbanding". See Locator object for further details.