Subtract Rectangle from Selection in GIMP

In GIMP, modifying existing selections is an essential technique for precise photo editing and graphic design. This guide explains how to subtract a new rectangular shape from an active selection using keyboard shortcuts, detailing the exact keys to press, how the cursor indicates mode changes, and an alternative interface method to achieve the same result.

The Keyboard Shortcut

The primary keyboard shortcut to subtract a selection is holding the Ctrl key while using a selection tool.

To subtract a rectangular area from an existing selection:

1. Press R on your keyboard to activate the Rectangle Select Tool.
2. Press and hold the Ctrl key on your keyboard.
3. Look at your mouse cursor: a small minus sign (-) will appear next to the pointer, indicating that the tool is in Subtract from the current selection mode.
4. While continuing to hold Ctrl, click and drag over the active selection to define the rectangular area you wish to remove.
5. Release the left mouse button first to finalize the cut-out, then release the Ctrl key.

Alternative Method via Tool Options

If you prefer using the graphical interface rather than keyboard modifiers:

1. Select the Rectangle Select Tool from the Toolbox or press R.
2. Open the Tool Options panel (usually located beneath the Toolbox on the left).
3. Under the Mode section, click the third icon: Subtract from the current selection (represented by two overlapping squares where the front one is subtracted from the back one).
4. Click and drag over the active selection on your canvas to cut out the rectangle without needing to hold the Ctrl key.