CSS Animation Generator: Free Keyframe Builder

This CSS animation generator lets you pick one of 14 ready-made keyframe presets, adjust duration, delay, iteration count, timing and direction, watch a live preview, and copy clean CSS. It is built for developers and designers who want working @keyframes code in seconds, free and with no sign-in.

What Is a CSS Animation?

A CSS animation is motion defined entirely in a stylesheet. A @keyframes rule describes how properties change over time, and animation properties on an element tell the browser how to play that rule. No JavaScript is needed for the effect itself.

Keyframes work like waypoints. You set values at from and to, or at percentages between 0% and 100%, and the browser calculates every frame in between. The Fade In preset, for example, moves opacity from 0 to 1.

CSS Animation vs CSS Transition

A transition animates between two states when something triggers it, such as a hover. An animation plays from keyframes, can have many steps, and can start by itself and repeat.

If you only need a hover effect, a transition is simpler. For loaders, attention cues and entrance effects, an animation is the right choice.

How Do You Use the CSS Animation Generator?

You choose a preset, tune five settings, preview the motion and copy the code. The whole process takes under a minute.

1. Open Animation Preset and choose an effect, from Fade In and Slide In Left to Rubber Band and Heartbeat.
2. Drag Duration (s) between 0.1 and 5 seconds. The default is 1 second.
3. Drag Delay (s) between 0 and 5 seconds if the motion should wait before it starts.
4. Choose Iteration: 1, 2, 3 or Infinite.
5. Pick a Timing option (ease, ease-in, ease-out, ease-in-out or linear) and a Direction (normal, reverse, alternate or alternate-reverse).
6. Click Play Animation to replay the preview box, then press Copy to take the code from the Generated CSS panel.

The Generated CSS panel updates as you move any control, so the code always matches your settings. It applies the animation to a class called animated-element. Rename it to match your own markup.

Worked Example: A Card That Slides Up and Settles

Say you want a pricing card to rise into place when the page loads. Choose Slide In Up, set Duration to 0.6, Delay to 0.2, Iteration to 1, Timing to ease-out and Direction to normal.

The panel shows the @keyframes slideInUp rule, which starts the element 50 pixels lower with opacity 0 and ends it in place at full opacity. Below it, the class receives animation-name: slideInUp; animation-duration: 0.6s; animation-delay: 0.2s; animation-iteration-count: 1; animation-timing-function: ease-out; animation-direction: normal;

In plain terms: after a 0.2 second wait, the card glides up and fades in over 0.6 seconds, moving fast at first and slowing as it lands. That feels natural for an entrance.

One catch: during the 0.2 second delay the card is visible in its normal position, then jumps to the start frame. To keep it hidden until the motion begins, add animation-fill-mode: backwards (or both) by hand.

What Does Each Setting Control?

Each control maps to one CSS animation property, and each changes how the motion feels.

Duration

Duration is the time one cycle takes. As a common rule of thumb, small interface motion feels right between 0.2 and 0.5 seconds, and entrance effects between 0.4 and 0.8 seconds. Anything longer than a second can feel sluggish unless it is a decorative or looping effect such as a spinner.

Delay

Delay is the wait before the first cycle. To stagger a list, give each item the same animation with a delay that grows by about 0.1 seconds per item.

Iteration

Iteration sets how many times the animation plays: 1, 2, 3 or Infinite. Use one play for entrances and Infinite for spinners and gentle pulses.

Timing

Timing controls the speed curve. Ease starts slow, speeds up and slows down. Ease-in starts slow, ease-out ends slow (good for entrances), and ease-in-out is symmetrical. Linear keeps a constant speed, which is what you want for a continuous spin.

Direction

Direction decides which way the keyframes run. Normal plays forward and reverse plays backward. Alternate goes forward, then back on the next cycle, and alternate-reverse starts backward. Alternate only shows its effect when Iteration is 2, 3 or Infinite.

Which Preset Fits Which Job?

Match the preset to the message you want the motion to send.

• Fade In and Fade Out: opacity only, the gentlest option. Good for tooltips, banners and modals.
• Slide In Left, Right, Up and Down: Left and Right travel the full width of the element, while Up and Down move 50 pixels. Good for panels, cards and toast messages.
• Zoom In: grows from scale 0 to full size. Suits dialogs and badges.
• Bounce, Pulse and Heartbeat: Bounce lifts 30 pixels, Pulse scales to 1.2 and Heartbeat gives two quick beats at 1.3. Use them to draw the eye to a button or notification dot.
• Shake: moves 10 pixels left and right. A clear signal for a form error.
• Spin and Flip: both rotate 360 degrees. Pair Spin with linear timing and Infinite iteration for a loading icon.
• Rubber Band: a squash-and-stretch effect for playful confirmations.

How Do You Make a CSS Animation Loop, Stay or Run Smoothly?

Looping is a dropdown choice, while staying at the end state and smoothness need a little extra CSS knowledge.

How do you make a CSS animation loop?

Set Iteration to Infinite. For effects that should move back and forth without snapping to the start, also set Direction to alternate.

How do you make a CSS animation stay at its end state?

By default an element returns to its original styles after the last cycle. Add animation-fill-mode: forwards to the generated class to hold the final frame. This matters most for Fade Out, where the element would otherwise reappear. The generator does not output this property, so add it yourself.

How do you make a CSS animation smooth?

All 14 presets change only transform and opacity, which browsers can usually animate without recalculating page layout. When you edit the code, avoid animating width, height, top or left. Also choose timing that fits the motion: linear for continuous rotation, ease-out for things arriving on screen.

Who Is a CSS Animation Builder Useful For?

Anyone who needs motion without writing keyframes from scratch will save time here.

• Front-end developers prototyping an entrance effect, then pasting the code into a component stylesheet.
• Designers who want to hand over exact durations and easing instead of a verbal description.
• Site owners adding a custom effect through a theme or custom CSS box.
• Students learning how keyframes work by changing a setting and reading how the code changes.
• Performance-minded teams who prefer lightweight CSS motion over a script library, since transform-based animation does not shift surrounding content.

Best Practices and Troubleshooting

Most problems come from a mismatch between the copied code and the page it lands on.

• Nothing animates: make sure the class in your HTML matches the one in the CSS, and that the @keyframes rule is included once in the same stylesheet.
• The preview did not replay: click Play Animation. The preview restarts each time you press it.
• Element flashes before sliding in: you have a delay without a fill mode. Add animation-fill-mode: backwards.
• Respect motion preferences: wrap a rule in a prefers-reduced-motion: reduce media query that sets animation to none. Our CSS media query generator can help you write the query.
• Do not animate everything: one or two moving elements guide attention, while ten compete for it.
• Keep the file lean: tidy pasted code with a CSS formatter while editing, and run the finished stylesheet through a CSS minifier before launch.
• Build a matching look: an animated card looks more finished with a layered shadow from the box shadow generator, or a backdrop from the CSS gradient generator.

What Are the Limits of This Tool?

The generator produces one animation at a time from 14 presets. It does not include a custom keyframe editor, cubic-bezier curves, multiple animations on one element, or a fill-mode setting.

To go beyond the presets, copy the code and edit it by hand. For example, change the 50 pixel offset in Slide In Up to 100 pixels for a longer travel. The preview is a single box, so always test the final result on your real element and at your real screen sizes.

With the right preset and a few setting changes, you can have production-ready keyframe code without typing it out. Set your options above, press Play Animation to check the motion, then copy the CSS into your project. For more helpers like this, browse the web developer tools collection.