CSS Animation Generator

What this generates

CSS @keyframes plus the matching animation shorthand, ready to drop into any stylesheet. Pick a preset, tune the parameters, watch the live preview, copy the result.

Ten presets cover the most common cases:

• fadeIn: opacity 0 → 1
• slideInLeft / Right / Up: translate from off-screen + fade in
• pulse: gentle scale pulse (good for attention-getting buttons)
• shake: horizontal shake (form errors, denial)
• bounce: vertical bounce
• spin: 360° rotation (loading spinners)
• wiggle: small tilt back and forth (notifications, hover effects)
• pop: scale up from 0 with a slight overshoot

Tunable parameters

• Duration: how long the animation runs, in seconds (0.1-10)
• Delay: wait this long before starting (useful for staggered animations)
• Easing: built-in CSS easing curves plus a “spring” cubic-bezier
• Iteration: finite count (1, 2, 3…) or infinite
• Direction: normal, reverse, alternate, alternate-reverse
• Restart: button to replay the animation from scratch when you change params

The live preview re-renders each time you change a parameter, so you can iterate fast.

When you’d use each preset

• fadeIn / slide variants: page-load entrance, modal appear, card mount
• pulse: highlighting a CTA, notification badges
• shake: form validation error, denial gesture
• bounce: success message, attention to a notification
• spin: loading state, refresh icon
• wiggle: hover effect on an icon, soft attention prompt
• pop: success badge appearing, modal “in”

Performance notes

For animations that run continuously (loading spinners, infinite pulses), you want them to be GPU-accelerated. The presets all use transform and opacity, these are the two properties browsers can animate without re-laying out the page. Animations on width, height, top, left are slow and should be avoided.

If you need smoothness:

• Use will-change: transform on heavy-animated elements (sparingly, overuse defeats the purpose)
• Keep animations short (under 0.5s for UI feedback, longer is fine for ambient)
• Test on mobile, desktop performance is misleading

Custom keyframes

The generator builds simple two-stop or multi-stop keyframes. For complex sequences (multiple intermediate stops, multiple properties animated together), you’ll need to hand-edit the output. The generated CSS is straightforward, find the @keyframes block and add stops.

Frequently asked questions

Why does my animation look stuttery? Likely you’re animating layout-affecting properties (width, height, padding) instead of transform. Switch to transform-based animations. Browsers can hardware-accelerate transforms but not layout properties.

Can I chain multiple animations? CSS supports multiple animations via comma-separated values: animation: fadeIn 0.3s, pulse 2s infinite. The generator builds one at a time, for chains, generate each separately and combine manually.

Will it work in older browsers? CSS animations are supported in IE10+, all modern browsers. No vendor prefixes needed in 2026.

How do I trigger the animation on hover or scroll? The generated CSS applies the animation immediately. For trigger-based animations, wrap the rule in :hover, or use IntersectionObserver to add a class on scroll-into-view. Both are out of scope for this generator.