Free modern CSS tool

CSS Scroll Timeline Generator

Scroll the demo panel to preview real scroll-driven CSS animations, tune the range, and copy working animation-timeline code.

Scroll inside the panel below to trigger the animation
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CSSScroll-driven element

This box animates purely with CSS as you scroll. No JavaScript scroll listeners are involved.

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Ready-to-use CSS

Motion that follows the scrollbar, not the clock

Build entrance animations that are perfectly in sync with how far someone has scrolled, without a single scroll event listener.

Real CSS, not JS

The preview is driven entirely by animation-timeline and animation-range — genuine scroll-linked CSS animation.

scroll() or view()

Compare a scroll-container-based timeline against a view-based timeline that reacts to the element itself entering the viewport.

Copy in one click

Grab the full @keyframes block plus the animation-timeline and animation-range declarations.

How to use the scroll timeline generator

  1. Pick an animationChoose fade-in, scale-in, slide-up or rotate-in for the demo element.
  2. Choose a timeline sourceSwitch between scroll() and view() and adjust the animation-range sliders.
  3. Scroll and copyScroll the demo panel to preview it live, then copy the generated CSS.

About scroll-driven CSS animations

Traditionally, CSS animations run on a fixed time-based clock: you set a duration and the animation plays from 0% to 100% regardless of what the user is doing on the page. Scroll-driven animations replace that clock with a scroll-based progress source using the animation-timeline property. A scroll() timeline maps 0% to 100% of the animation onto the scroll progress of a scrollable ancestor, so the animation plays forward as you scroll down and reverses as you scroll up. A view() timeline instead tracks how far the animated element itself has traveled through the nearest scrollport, which is usually the better choice for "reveal on scroll" effects because it triggers relative to the element's own position rather than the container's total scroll distance. The animation-range property narrows or shifts exactly which portion of that timeline the animation plays across, so you can make an element finish animating well before it reaches the center of the viewport, for example.

No JS scroll listeners

The browser drives the animation directly on the compositor, which is typically smoother than a scroll event handler.

animation-range matters

A narrow range like 0% to 40% finishes the animation quickly; a wide range stretches it across more scroll distance.

Pair with prefers-reduced-motion

Wrap scroll-driven animations in an @media (prefers-reduced-motion: no-preference) query out of respect for motion-sensitive users.

CSS scroll timeline generator FAQ

What is animation-timeline in CSS?

animation-timeline is a CSS property that lets an animation's progress be driven by something other than time, such as the scroll position of a container (scroll()) or how far an element has scrolled into view (view()), instead of a fixed duration.

What is the difference between scroll() and view()?

scroll() maps the animation to the scroll progress of a scrollable ancestor from 0% to 100% of its scroll range. view() maps the animation to how far the animated element itself has traveled through the visible scrollport, which is usually better for triggering an animation as an element enters and leaves the viewport.

What does animation-range control?

animation-range sets the start and end points of the timeline, as percentages, over which the animation plays. Narrowing the range makes the animation play faster over a shorter scroll distance instead of stretching across the whole timeline.

Are scroll-driven animations supported in all browsers?

Scroll-driven animations have broad support in Chromium-based browsers such as Chrome and Edge. Support is still expanding in other engines, so for production use it is worth checking current browser support and providing a fallback.

How do I add a fallback for unsupported browsers?

A common fallback is to detect support with CSS.supports('animation-timeline: scroll()') and, if it returns false, use an IntersectionObserver in JavaScript to add or remove a class that triggers a regular time-based CSS transition or animation instead.

Try other tools

Keep building with these free online CSS tools.

KFAnimation Keyframe VisualizerBuild motion on a visual timeline. GRDCSS Gradient GeneratorDesign smooth color gradients. SHDCSS Shadow GeneratorLayer soft, realistic shadows.