Core Tools

Using the brush tool

Erase and restore areas of your cutout with a precision brush with adjustable size, hardness, and opacity.

Overview

The brush tool lets you manually refine the AI cutout. It operates in two modes:

  • Erase — makes areas transparent (removes them from the cutout)
  • Restore — brings back the original pixels (adds them back to the cutout)

The brush is non-destructive: it works on the mask layer separately from your original image. You can always undo, and the original image data is never modified.

Opening the editor

After the AI processes your image, click the thumbnail in the queue to open the editor. The brush tool is in the left sidebar.

Keyboard shortcuts

ActionShortcut
Activate brushB
Erase modeE
Restore modeR
Increase brush size]
Decrease brush size[
UndoCtrl+Z / Cmd+Z
RedoCtrl+Shift+Z / Cmd+Shift+Z

Brush controls

Size

Ranges from 1 px to 500 px. Use small sizes (5–20 px) for detailed edge work and large sizes (100–500 px) for removing large unwanted areas quickly.

Tip: Use [ and ] to adjust size without leaving the canvas.

Hardness

Controls the edge of the brush stroke:

  • 100% — hard edge, sharp cutoff (good for objects with clear boundaries)
  • 0% — fully soft/feathered edge, Gaussian falloff (good for hair, fur, semi-transparent areas)

For most edge work, 50–70% hardness gives a good balance. Use lower hardness near soft edges like hair.

Opacity

Controls how strongly each stroke affects the mask:

  • 100% — fully erases or restores in a single stroke
  • 50% — partial effect, allowing you to build up transparency gradually
  • 20% — very subtle, useful for blending near soft edges

Low-opacity restore strokes are especially useful for bringing back semi-transparent areas that the AI removed too aggressively.

Pressure sensitivity

If you're using a drawing tablet (Wacom, XP-Pen, Huion) or an iPad with Apple Pencil, brush pressure automatically scales the opacity. Press harder for stronger strokes, lighter for softer ones.

Practical tips

Fixing over-erased hair

Switch to Restore mode, set hardness to 20–40%, opacity to 40–60%, and gently paint over the lost strands. The original hair data is still there — you're just increasing its opacity.

Removing a stubborn background patch

Switch to Erase mode, set hardness to 80–100% for objects with clear edges. Use a smaller brush to trace around the edge of the subject. Zoom in with the scroll wheel to get precision.

Cleaning up fringing

If you see a colour halo around edges, the Decontaminate setting in Edge Refinement often fixes it without manual brush work. See Edge refinement.

Brush vs edge refinement

The brush is for large-area corrections and hard-to-fix regions. For systematic edge improvement (feathering, smoothing, expanding), use Edge Refinement first — it's faster.

Undo/redo

Every completed brush stroke is a single history entry. You can undo up to 50 strokes. Use Ctrl+Z / Cmd+Z to undo and Ctrl+Shift+Z / Cmd+Shift+Z to redo.

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