Tool manual

How to use the Magnetic Lasso tool

The Magnetic Lasso tool snaps its line to the nearest strong edge as you move along it, so you can select an object with a clear outline without tracing it exactly.

Where to find it

It is in the toolbar, in one slot with Lasso and Polygonal Lasso. Right-click the slot, or press and hold it, to choose between them. Press Shift+L until it is selected (L on its own picks Lasso).

How to use it

1. Choose the tool. Press Shift+L until it is selected, or right-click the lasso slot and pick Magnetic Lasso.
2. Click on the edge. Click once on the edge of the object to start.
3. Move along the edge. Move the pointer along the outline without holding the button. The line hugs the edge and drops anchor points as it goes.
4. Help it at corners. Click to drop your own anchor where the edge turns sharply. Backspace removes the last anchor.
5. Close it. Click the start point, double-click, or press Enter. Esc cancels.

Options bar settings

• Width: How far from the pointer, in pixels, the tool looks for an edge. Smaller is more precise; larger forgives a shaky hand.
• Contrast: How strong an edge must be before the line follows it. Raise it when the line jumps to texture in the background.
• Frequency: How often anchor points are dropped. Higher puts them closer together, which helps on curvy edges.

Tips and common mistakes

• The options bar has no New or Add buttons for this tool, but the keys still work: hold Shift at the first click to add, Alt to subtract.
• It works best on edges with clear contrast. On soft or busy edges, Quick Selection or Object Selection is usually faster.

Related

• How to use the Lasso tool
• How to use the Quick Selection tool
• How to use the Object Selection tool

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Checked 13 November 2026 in the current editor.

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