How to Use the Lasso Selection Tool in Paint.NET

This article explains how to use the lasso selection tool in Paint.NET, which is used to draw freehand selections. Instructions apply to version 4.2 of the Paint.NET image editing software for Windows, not to be confused with the website of the same name.

How to Use the Lasso Tool in Paint.NET

To select a specific area of an image using the lasso select tool:

1. Go to Tools > Lasso Select, or select the lasso icon in the toolbar.

2. Press and hold the mouse button while moving the cursor to select the area you want. As you draw, the selected area is identified by a thin borderline and a transparent blue overlay.

3. You can then copy, cut, or move your selection.

Lasso Select Tool Options

While a tool is active, the icons beside Tools change to display all available options. In this case, the only option is the selection mode. By default, this will be set to Replace. In this mode, every time you click to start drawing a new selection, any existing selections are removed from the document. Hover your mouse cursor over the different icons to see what each one does.

• Add (union): Any existing selections will remain active along with a newly drawn selection. This mode can be used to draw lots of small selections that will slowly combine to form a larger, more complex selection. Zooming in and drawing small selections is generally easier and more accurate than trying to draw a selection in one go.
• Subtract: This option does the opposite of Add (union) mode, so it can be used to fine tune a selection by removing areas that have been accidentally included within the selected area.
• Intersect: This setting will only function if there is an existing active selection in the document. Otherwise, the selection will disappear as soon as the mouse button is released. If there is an active selection, only the areas that fall within both the active selection and the new selection will be selected.
• Invert ("xor): This setting works like the Intersect setting in reverse. If the there is an active selection already in the document, any areas of that selection that fall within the new selection will be removed from the selection, while the other areas will remain selected.

While Paint.NET lacks a bezier line tool, zooming in and using the Add (union) and Subtract options allows you to build up more elaborate selections of pixels. If you're not comfortable with using bezier line tools, this may actually be a more attractive way to make a selection.