Definition
A keyframe is a specific frame in a sequence that defines a significant moment of change — a start point, an end point, or a critical position within a movement. In animation, keyframes mark the essential poses that define a character's action, with the intermediate frames (called "in-betweens" or "tweens") filling in the smooth motion between them.
The concept applies across multiple disciplines: hand-drawn animation, 3D animation, motion graphics, video editing, and even storyboarding.
Keyframes in Animation
In traditional animation, a lead animator draws the key poses — the frames that define the character's movement. These are the keyframes. Assistant animators then draw the in-between frames that create smooth motion from one key pose to the next.
For example, a character throwing a punch might have these keyframes:
- Anticipation — the character pulls their fist back
- Contact — the fist strikes the target
- Follow-through — the arm extends past the contact point
- Recovery — the character returns to a resting pose
Everything between these four poses is interpolated, either by an in-between artist (traditional) or by software (digital).
In 3D animation and motion graphics, keyframes work similarly. The animator sets values (position, rotation, scale, opacity) at specific frames, and the software calculates the transitions between them using interpolation curves.
Keyframes in Storyboarding
In storyboarding, a keyframe refers to a panel that captures a pivotal visual moment in a scene. Not every moment in a scene needs a storyboard panel — keyframes are the moments where something visually changes or emotionally shifts.
A storyboard keyframe might represent:
- The first composition of a new scene (establishing shot)
- A character's reaction at a crucial story beat
- The peak of an action sequence
- A camera angle change that reveals new information
- The final image of a scene before a transition
Experienced storyboard artists know which moments are keyframes (must be drawn) and which are in-betweens (implied by the surrounding panels).
Keyframes in Video Editing
In video editing and compositing software, keyframes mark points where a parameter changes value over time. An editor might set a keyframe for an image's opacity at 0% (invisible), then set another keyframe two seconds later at 100% (fully visible), creating a fade-in effect.
Why Keyframes Matter
Keyframes are the decision points of visual storytelling. They represent the moments where a conscious creative choice is made about position, timing, expression, or composition. Everything between keyframes is mechanical interpolation. The keyframes themselves are where the artistry lives.
In storyboarding, identifying the right keyframes — the moments that truly matter — is the skill that separates efficient, effective storyboards from over-detailed or under-detailed ones.
Genkee's Storyboard Agent helps identify keyframes in your script by analyzing story beats and suggesting which moments deserve dedicated storyboard panels, focusing your effort on the frames that matter most.