GSAP Performance

When to Use This Skill

Apply when optimizing GSAP animations for smooth 60fps, reducing layout/paint cost, or when the user asks about performance, jank, or best practices for fast animations.

Related skills: Build animations with gsap-core (transforms, autoAlpha) and gsap-timeline; for ScrollTrigger performance see gsap-scrolltrigger.

Prefer Transform and Opacity

Animating transform (

x

,

y

,

scaleX

,

scaleY

,

rotation

,

rotationX

,

rotationY

,

skewX

,

skewY

) and opacity keeps work on the compositor and avoids layout and most paint. Avoid animating layout-heavy properties when a transform can achieve the same effect.

• ✅ Prefer: x, y, scale, rotation, opacity.
• ❌ Avoid when possible: width, height, top, left, margin, padding (they trigger layout and can cause jank).

GSAP’s x and y use transforms (translate) by default; use them instead of left/top for movement.

will-change

Use will-change in CSS on elements that will animate. It hints the browser to promote the layer.

will-change: transform;

Batch Reads and Writes

GSAP batches updates internally. When mixing GSAP with direct DOM reads/writes or layout-dependent code, avoid interleaving reads and writes in a way that causes repeated layout thrashing. Prefer doing all reads first, then all writes (or let GSAP handle the writes in one go).

Many Elements (Stagger, Lists)

• Use stagger instead of many separate tweens with manual delays when the animation is the same; it’s more efficient.
• For long lists, consider virtualization or animating only visible items; avoid creating hundreds of simultaneous tweens if it causes jank.
• Reuse timelines where possible; avoid creating new timelines every frame.

Frequently updated properties (e.g. mouse followers)

Prefer gsap.quickTo() for properties that are updated often (e.g. mouse-follower x/y). It reuses a single tween instead of creating new tweens on each update.

let xTo = gsap.quickTo("#id", "x", { duration: 0.4, ease: "power3" }),
    yTo = gsap.quickTo("#id", "y", { duration: 0.4, ease: "power3" });

document.querySelector("#container").addEventListener("mousemove", (e) => {
  xTo(e.pageX);
  yTo(e.pageY);
});

ScrollTrigger and Performance

• pin: true promotes the pinned element; pin only what’s needed.
• scrub with a small value (e.g.

  scrub: 1

  ) can reduce work during scroll; test on low-end devices.
• Call ScrollTrigger.refresh() only when layout actually changes (e.g. after content load), not on every resize; debounce when possible.

Reduce Simultaneous Work

• Pause or kill off-screen or inactive animations when they’re not visible (e.g. when the user navigates away).
• Avoid animating huge numbers of properties on many elements at once; simplify or sequence if needed.

Best practices

• ✅ Animate transform and opacity; use will-change in CSS only on elements that animate.
• ✅ Use stagger instead of many separate tweens with manual delays when the animation is the same.
• ✅ Use gsap.quickTo() for frequently updated properties (e.g. mouse followers).
• ✅ Clean up or kill off-screen animations; call ScrollTrigger.refresh() when layout changes, debounced when possible.

Do Not

• ❌ Animate width/ height/ top/ left for movement when x/ y/ scale can achieve the same look.
• ❌ Set will-change or force3D on every element “just in case”; use for elements that are actually animating.
• ❌ Create hundreds of overlapping tweens or ScrollTriggers without testing on low-end devices.
• ❌ Ignore cleanup; stray tweens and ScrollTriggers keep running and can hurt performance and correctness.