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The Magnetic Lasso improves upon the regular Lasso by allowing the selection outline to seek the nearest edge.

Like the Magnetic Pen, this tool sets "fastening points" that seek high-contrast regions, and joins the points with border segments. Unlike the pen, the lasso fastening points disappear immediately, and thus cannot be moved after being set.


  • Selection tool common options
Similar to a brush width, and can be changed using the same hotkeys. The larger the width, the further away from the cursor the tool will search.
Determines how much the color values must differ—within the tool width—in order to be considered. If no such region can be found, the next fastening point will be at the cursor.
Determines how often a fastening point will be laid.
Stylus Pressure
Causes the tool to be more precise when more pressure is applied—the tool width will decrease.


The Magnetic Lasso cannot be used with images that use 32-bit color channels.

See also[]

  • Magnetic Pen, which uses a similar algorithm to set fastening points for a vector path.