Xerobit

CSS Animation Generator: Keyframes and Shorthand Code

This css animation generator builds complete @keyframes rules and animation shorthand declarations from common presets. Choose an effect, set the duration, delay, timing function, iteration count and direction, then copy the output directly into your stylesheet. Everything runs in the browser so nothing is uploaded to a server.

Generated CSS

@keyframes animated-element {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.animated-element {
  animation: animated-element 1s ease 0s 1 normal both;
}
  • Preset
    Fade
  • Duration
    1s
  • Delay
    0s
  • Timing
    ease
  • Iterations
    1
  • Direction
    normal
  • Fill mode
    both

How to use the css animation generator

  1. Select an animation preset such as fade, slide, bounce, pulse, spin or shake.
  2. Adjust the duration and delay values in seconds to control the pacing.
  3. Choose a timing function, iteration count, direction and fill mode for fine-tuned behaviour.
  4. Enter a valid CSS class name that will be used for both the selector and the keyframes identifier.
  5. Copy the generated @keyframes block and animation shorthand into your stylesheet.

How the CSS animation shorthand works

The animation shorthand combines up to eight individual properties into a single declaration. The order matters when two time values are present: the first is always animation-duration and the second is animation-delay. The full syntax is:

animation: name duration timing-function delay iteration-count direction fill-mode play-state;

For example, if you set a 1.5 second duration, a 0.2 second delay, linear timing, three iterations and alternate direction on a class called .card, this css animation generator outputs:

animation: card 1.5s linear 0.2s 3 alternate both;

The fill-mode value both ensures the element retains the styles from the first keyframe before the delay starts and the last keyframe after the animation ends.

Understanding @keyframes blocks

A css keyframes generator produces the @keyframes rule that defines what changes at each point in the timeline. Percentages mark the progress from 0% (or from) to 100% (or to). Each preset in this tool uses specific transform and opacity values:

Preset0%50%100%
Fadeopacity: 0opacity: 1
SlidetranslateY(40px), opacity: 0translateY(0), opacity: 1
BouncetranslateY(0)translateY(-30px)translateY(0)
Pulsescale(1)scale(1.05)scale(1)
Spinrotate(0deg)rotate(360deg)
ShaketranslateX(0)translateX(-10px) at 25%, translateX(10px) at 75%translateX(0)

You can edit these values after copying the code to match your exact design requirements.

Practical use cases for CSS animations

Animations improve perceived performance and guide user attention without JavaScript overhead. Common scenarios include:

  • Loading indicators: A spin preset with infinite iterations and linear timing creates a smooth, continuous rotation for loading icons.
  • Form validation feedback: The shake preset draws attention to an invalid input field. Pair it with a short duration of 0.3 to 0.5 seconds so the motion feels snappy rather than distracting.
  • Page entry effects: Fade and slide presets work well for content that appears on scroll or page load. Use forwards or both fill mode so the element stays visible after the animation completes.
  • Call-to-action emphasis: A subtle pulse animation on a button encourages clicks. Keep the scale change small (1.05 to 1.1) to avoid layout shifts.

This animation css generator covers all of these patterns out of the box.

Common mistakes and how to avoid them

Several pitfalls cause animations to fail silently or behave unexpectedly:

  • Missing vendor prefixes: Modern browsers support unprefixed @keyframes and animation, but if you need to support very old Safari versions, add -webkit- prefixes manually.
  • Conflicting transitions: If the same property is controlled by both a transition and an animation, the animation takes precedence during its active phase but the transition may interfere afterward. Remove the transition or scope it to different properties.
  • Invalid class names: CSS identifiers cannot start with a digit or contain spaces. This tool validates the class name to prevent syntax errors.
  • Layout thrashing: Animating properties like width, height or margin forces the browser to recalculate layout every frame. Stick to transform and opacity for smooth 60fps results, which is why all presets here use those properties exclusively.

Combining with other CSS tools

Once you have your animation code, you might want to clean up or extend your stylesheet. Run the output through a css formatter to align it with your project's style conventions. If you are migrating a legacy codebase, the scss to css converter or less to css converter can help you move preprocessor files to standard CSS before adding new animations.

For visual polish, pair your animated elements with effects from the box shadow generator or the glassmorphism css generator. When responsiveness matters, use the css clamp generator to size elements fluidly so the animation proportions remain consistent across viewports.

Worked examples

ExampleInputResult
Fade in over half a secondAnimation preset: fade; Duration (seconds): 0.5; Delay (seconds): 0; Timing function: ease-in; Iteration count: 1; Direction: normal; Fill mode: forwards; Class name: fade-boxPreset: Fade; Duration: 0.5s; Delay: 0s; Timing: ease-in; Iterations: 1; Direction: normal; Fill mode: forwards
Infinite spinning loaderAnimation preset: spin; Duration (seconds): 1.5; Delay (seconds): 0; Timing function: linear; Iteration count: infinite; Direction: normal; Fill mode: none; Class name: loaderPreset: Spin; Duration: 1.5s; Delay: 0s; Timing: linear; Iterations: infinite; Direction: normal; Fill mode: none
Delayed bouncing alertAnimation preset: bounce; Duration (seconds): 0.8; Delay (seconds): 0.3; Timing function: ease; Iteration count: 3; Direction: normal; Fill mode: both; Class name: alert-bouncePreset: Bounce; Duration: 0.8s; Delay: 0.3s; Timing: ease; Iterations: 3; Direction: normal; Fill mode: both

FAQ

What is a css animation generator?

A css animation generator is a tool that writes the @keyframes rule and the animation shorthand property for you. You pick an effect and configure timing options, and it outputs valid CSS ready to paste into your stylesheet.

Can I use this as a css keyframes generator only?

Yes. The output always includes the standalone @keyframes block at the top. You can copy just that portion if you prefer to write the animation property yourself or apply it differently.

Do these animations require JavaScript?

No. Everything produced by this animation css generator is pure CSS. The browser handles the animation loop natively using the compositor thread, which means no JavaScript runtime cost.

Why does the bounce preset use translateY instead of top or margin?

Transform properties like translateY are handled by the GPU compositor and do not trigger layout recalculations. Animating top or margin causes reflows on every frame, resulting in janky motion especially on mobile devices.

What does the fill mode setting do?

Fill mode controls the element's styles before and after the animation plays. The value 'both' applies the 0% keyframe styles during any delay period and keeps the 100% keyframe styles after the animation finishes.

Is the generated CSS compatible with all modern browsers?

Yes. The output uses standard, unprefixed CSS animation syntax supported by Chrome, Firefox, Safari and Edge. Vendor prefixes are only needed for very old browser versions.

Can I animate multiple properties at once?

The presets focus on one primary effect to keep the code simple. After copying the output, you can add extra properties inside the @keyframes percentages, such as combining opacity with transform for a fade-and-slide effect.