How to Add and Use Keyframes in After Effects (Beginner Guide)

Keyframes are the foundation of ALL animation in After Effects. A keyframe marks a specific value at a specific time — After Effects fills in the movement between them.

The concept:
Imagine your object is at position X=100 at 0 seconds, and X=500 at 2 seconds. AE automatically calculates all the positions between those two points. Each marked position is a "keyframe."

How to add keyframes:
1. Select your layer
2. Press the shortcut for the property you want to animate:
- P = Position
- S = Scale
- R = Rotation
- T = Opacity (T for Transparency)
- A = Anchor Point
3. Move the playhead to your START time
4. Click the ⏱️ stopwatch icon next to the property name — this sets your FIRST keyframe
5. Move the playhead to your END time
6. Change the value (drag in the viewer or type a new number)
7. A second keyframe is automatically created

Essential shortcuts:
- U = Show only properties with keyframes (on selected layer)
- J / K = Jump to previous / next keyframe
- Ctrl/Cmd + Shift + K = Keyframe velocity dialog
- F9 = Easy Ease selected keyframes

Modifying keyframes:
- Move: Click and drag a keyframe diamond in the timeline
- Delete: Select and press Delete
- Copy/Paste: Select keyframes → Ctrl/Cmd+C, move playhead, Ctrl/Cmd+V
- Select all keyframes on a property: Click the property name

Important rule: The stopwatch toggles keyframing ON/OFF for that property. Clicking it again deletes ALL keyframes for that property. Don't click it twice!

Pro tip: After setting your keyframes, ALWAYS apply Easy Ease (F9) before previewing. Linear keyframes look robotic. Easy Ease is your minimum baseline for smooth motion.