How to Smooth Curves in Blender Graph Editor

This guide explains how to smooth animation curves (F-Curves) using Blender's Graph Editor. You will learn the most effective methods to remove jitter and achieve fluid motion, including using built-in smoothing operators, adjusting keyframe handle types, and applying non-destructive curve modifiers.

1. Using the Smooth Keys Operator

The fastest way to smooth out jagged keyframes directly on an animation curve is using the built-in Smooth Keys tool.

  1. Switch to the Graph Editor workspace.
  2. Select the channels or individual animation curves you want to smooth.
  3. Box-select the keyframes you wish to adjust.
  4. Press Alt + O (or go to Key > Smooth Keys in the top menu).
  5. Repeat the shortcut multiple times to increase the smoothing effect.
  6. Open the Operator Panel in the bottom-left corner of the viewport immediately after running the command to fine-tune the Factor and Iterations.

2. Using the Gaussian Smooth Filter

Blender includes an advanced Gaussian blur filter designed for motion capture cleanup and dense keyframe data.

  1. Select the target keyframes in the Graph Editor.
  2. Go to Key > Filter Keys > Smooth (Gaussian).
  3. In the pop-up settings in the bottom-left corner, adjust:
    • Factor: Controls the strength of the smoothing effect.
    • Sigma: Sets the width of the Gaussian blur blur kernel.
    • Filter Time: Toggles smoothing across the time axis.

3. Adjusting Keyframe Handle Types

Jerkiness in animation curves often results from misaligned or sharp Bezier handles. Changing handle types creates natural transitions between keyframes.

  1. Select the keyframes on your curve.
  2. Press V to open the Set Keyframe Handle Type menu.
  3. Choose one of the following options:
    • Automatic: Smooths the curve automatically based on adjacent keyframe positions.
    • Auto Clamped: Smooths curves while preventing overshoot beyond the keyframe values.
    • Aligned: Keeps handles locked in a straight 180-degree line to ensure seamless velocity transitions without abrupt angle changes.

4. Decimating and Cleaning Dense Keyframes

If raw keyframe density prevents smooth interpolation (common with baked physics or motion capture), clean the curve before smoothing.

  1. Select the dense keyframes.
  2. Go to Key > Decimate (Ratio) or Decimate (Error).
  3. Adjust the threshold in the operator box to remove redundant keys while preserving the overall curve shape.
  4. Apply Alt + O to the remaining keys to finalize the smoothing.

5. Applying a Smooth F-Curve Modifier

For a non-destructive approach that preserves your original keyframes, use an F-Curve modifier.

  1. Select the specific animation curve channel on the left sidebar of the Graph Editor.
  2. Press N to open the right-side properties panel and switch to the Modifiers tab.
  3. Click Add Modifier and select Smooth.
  4. Adjust the Smooth Factor and Iterations to dynamically filter out high-frequency noise without altering original key positions.