How to Smooth Grease Pencil Lines in Blender

Smoothing Grease Pencil lines in Blender allows you to eliminate jittery hand-drawn strokes and create clean, polished 2D artwork. This guide explains how to access the Smooth brush in Sculpt Mode, customize its settings for precise control, and use quick shortcuts to smooth strokes dynamically while drawing.

Method 1: Using the Smooth Tool in Sculpt Mode

Grease Pencil has a dedicated Sculpt Mode designed specifically for manipulating stroke geometry without altering your original drawings destructively.

  1. Select the Grease Pencil Object: In the 3D Viewport, click on the Grease Pencil object you want to modify.
  2. Enter Sculpt Mode: Click the mode dropdown menu in the top-left corner of the 3D Viewport (which defaults to Object Mode or Draw Mode) and select Sculpt Mode.
  3. Select the Smooth Brush: From the toolbar on the left side of the viewport, select the Smooth tool (represented by a wavy, relaxed line icon).
  4. Apply Smoothing: Click and drag your cursor over the vertices and lines you wish to relax. The brush will redistribute points and remove sharp angles.

Method 2: The Shift Key Quick-Smooth Shortcut

You do not need to switch tools every time you want to smooth out a line. Blender includes a global modifier key to trigger smoothing on the fly.

  • In Sculpt Mode: While using any other sculpting brush (such as Push, Grab, or Pinch), hold down Shift and drag over your strokes. Releasing Shift returns you to the active brush.
  • In Draw Mode: While drawing with standard stroke brushes, you can hold Shift after placing a stroke (or switch temporarily to Sculpt Mode) to instantly relax points on active layers.

Customizing Smooth Brush Settings

Adjusting the brush parameters allows you to control how aggressively the stroke geometry is modified.

  • Radius (F): Determines the size of the brush influence area. Press F and move the mouse to resize.
  • Strength (Shift + F): Controls the intensity of the smoothing effect per stroke pass. Press Shift + F to adjust.
  • Affect Options (Brush Settings Panel): In the top tool settings bar or the Properties Panel > Active Tool:
    • Position: Smooths the curvature and line shape (enabled by default).
    • Thickness: Equalizes stroke thickness variations across the selected area.
    • Strength/Opacity: Blends the transparency values along the stroke points.
    • UV: Smooths the distribution of texture mapping across the stroke.

Automatic Post-Draw Smoothing

If you prefer lines to smooth automatically immediately after drawing:

  1. Switch to Draw Mode.
  2. Select your drawing brush.
  3. Open the Tool panel on the right (press N if hidden).
  4. Under the Post-Processing tab, check the box for Smooth.
  5. Increase the Iterations value to automatically reduce stroke jitter whenever a line is completed.