CSS3 Transitions vs jQuery Animations
In this page:
// CSS does the animation
#element {
transition: property duration timing-function;
}
$("#element").toggleClass("class-name");
// jQuery does the animation
$("#element").animate({property: value}, duration);
CSS Transitions
CSS transitions let the browser animate a property change declaratively and are usually the lightest option for simple hover or state-based effects, since the browser's own rendering engine handles the animation.
Example: CSS Transitions
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<style>
#box { background:steelblue; color:#1a1a1a; padding:10px; border-radius:4px; display:inline-block; margin:10px 0; }
button { padding:6px 14px; margin:4px; background:#2c6aa0; color:white; border:none; border-radius:4px; cursor:pointer; }
#resetBtn { background:white; color:#2c6aa0; border:1px solid #2c6aa0; }
#output { margin-top:10px; padding:8px; border:1px solid #ccc; border-radius:4px; background:#f7f7f7; font-family:monospace; min-height:24px; }
#demo :where(p, div, span, li, h1, h2, h3, h4, td, th, blockquote, label, section, article, aside) { border:1px solid #4a7fb5; background:#eaf2fb; padding:6px 10px; margin:4px 0; border-radius:4px; }
#demo :where(ul, ol) { border:1px dashed #888; background:#fafafa; padding:8px 8px 8px 32px; margin:6px 0; }
#demo :where(table) { border-collapse:collapse; }
#demo :where(td, th) { border-radius:0; }
#demo :where(input, select, textarea) { margin:4px 0; }
</style>
</head>
<body>
<button id="resetBtn">Reset</button>
<section id="demo">
<style>#box { width:100px; transition: width 0.5s; }</style>
<div id="box">Box</div>
<button id="btn">Grow</button>
</section>
<div id="output"></div>
<script>
var original = $("#demo").html();
function init() {
$("#btn").on("click", function() {
$("#box").css("width", "300px");
});
}
init();
$("#resetBtn").click(function() {
$("#demo").html(original);
$("#output").empty();
init();
});
</script>
</body>
</html>
jQuery Animation
jQuery's animate() is useful when the animation itself needs to be driven by JavaScript logic -- for example, animating to a value calculated at runtime that CSS alone has no way to know about.
Example: jQuery Animation
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<style>
#box { background: steelblue; color: #1a1a1a; padding: 10px; border-radius: 4px; }
</style>
<style>
button { padding:6px 14px; margin:4px; background:#2c6aa0; color:white; border:none; border-radius:4px; cursor:pointer; }
#resetBtn { background:white; color:#2c6aa0; border:1px solid #2c6aa0; }
#output { margin-top:10px; padding:8px; border:1px solid #ccc; border-radius:4px; background:#f7f7f7; font-family:monospace; min-height:24px; }
#demo :where(p, div, span, li, h1, h2, h3, h4, td, th, blockquote, label, section, article, aside) { border:1px solid #4a7fb5; background:#eaf2fb; padding:6px 10px; margin:4px 0; border-radius:4px; }
#demo :where(ul, ol) { border:1px dashed #888; background:#fafafa; padding:8px 8px 8px 32px; margin:6px 0; }
#demo :where(table) { border-collapse:collapse; }
#demo :where(td, th) { border-radius:0; }
#demo :where(input, select, textarea) { margin:4px 0; }
</style>
</head>
<body>
<button id="resetBtn">Reset</button>
<section id="demo">
<div id="box" style="width:100px">Box</div>
<button id="btn">Animate to Random Width</button>
<div id="output"></div>
</section>
<script>
var original = $("#demo").html();
function init() {
$("#btn").on("click", function() {
const target = Math.random() * 200 + 100;
$("#output").text("Animating to " + Math.round(target) + "px");
$("#box").animate({width: target + "px"});
});
}
init();
$("#resetBtn").click(function() {
$("#demo").html(original);
$("#output").empty();
init();
});
</script>
</body>
</html>
CSS Class Toggle
A common hybrid pattern is using jQuery only to toggle a CSS class on and off, while the actual transition timing and easing are defined in a CSS rule -- combining jQuery's event handling with the browser's more efficient transition engine.
Example: CSS Class Toggle
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<style>
#box { background:steelblue; color:#1a1a1a; padding:10px; border-radius:4px; display:inline-block; margin:10px 0; }
button { padding:6px 14px; margin:4px; background:#2c6aa0; color:white; border:none; border-radius:4px; cursor:pointer; }
#resetBtn { background:white; color:#2c6aa0; border:1px solid #2c6aa0; }
#output { margin-top:10px; padding:8px; border:1px solid #ccc; border-radius:4px; background:#f7f7f7; font-family:monospace; min-height:24px; }
#demo :where(p, div, span, li, h1, h2, h3, h4, td, th, blockquote, label, section, article, aside) { border:1px solid #4a7fb5; background:#eaf2fb; padding:6px 10px; margin:4px 0; border-radius:4px; }
#demo :where(ul, ol) { border:1px dashed #888; background:#fafafa; padding:8px 8px 8px 32px; margin:6px 0; }
#demo :where(table) { border-collapse:collapse; }
#demo :where(td, th) { border-radius:0; }
#demo :where(input, select, textarea) { margin:4px 0; }
</style>
</head>
<body>
<button id="resetBtn">Reset</button>
<section id="demo">
<style>.active { background: yellow; transition: background 0.3s; }</style>
<div id="box">Box</div>
<button id="btn">Toggle</button>
</section>
<div id="output"></div>
<script>
var original = $("#demo").html();
function init() {
$("#btn").on("click", function() {
$("#box").toggleClass("active");
});
}
init();
$("#resetBtn").click(function() {
$("#demo").html(original);
$("#output").empty();
init();
});
</script>
</body>
</html>
Choose the Right Tool
As a rule of thumb, reach for CSS transitions when the effect is simple and state-based, and reach for jQuery's animate() when the animation depends on values or conditions computed in JavaScript.
Example: Choose the Right Tool
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<style>
#box { background:steelblue; color:#1a1a1a; padding:10px; border-radius:4px; display:inline-block; margin:10px 0; }
button { padding:6px 14px; margin:4px; background:#2c6aa0; color:white; border:none; border-radius:4px; cursor:pointer; }
#resetBtn { background:white; color:#2c6aa0; border:1px solid #2c6aa0; }
#output { margin-top:10px; padding:8px; border:1px solid #ccc; border-radius:4px; background:#f7f7f7; font-family:monospace; min-height:24px; }
#demo :where(p, div, span, li, h1, h2, h3, h4, td, th, blockquote, label, section, article, aside) { border:1px solid #4a7fb5; background:#eaf2fb; padding:6px 10px; margin:4px 0; border-radius:4px; }
#demo :where(ul, ol) { border:1px dashed #888; background:#fafafa; padding:8px 8px 8px 32px; margin:6px 0; }
#demo :where(table) { border-collapse:collapse; }
#demo :where(td, th) { border-radius:0; }
#demo :where(input, select, textarea) { margin:4px 0; }
</style>
</head>
<body>
<button id="resetBtn">Reset</button>
<section id="demo">
<style>#box { transition: opacity 0.3s; }</style>
<div id="box">Simple hover fade via CSS</div>
</section>
<div id="output"></div>
<script>
var original = $("#demo").html();
function init() {
$("#box").on("mouseenter", function() {
$(this).css("opacity", 0.5);
});
}
init();
$("#resetBtn").click(function() {
$("#demo").html(original);
$("#output").empty();
init();
});
</script>
</body>
</html>
Combining CSS and jQuery
It's common to split responsibilities: use jQuery to detect events and decide when something should happen, and let CSS handle how the resulting visual transition actually looks.
Example: Combining CSS and jQuery
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<style>
button { padding:6px 14px; margin:4px; background:#2c6aa0; color:white; border:none; border-radius:4px; cursor:pointer; }
#resetBtn { background:white; color:#2c6aa0; border:1px solid #2c6aa0; }
#output { margin-top:10px; padding:8px; border:1px solid #ccc; border-radius:4px; background:#f7f7f7; font-family:monospace; min-height:24px; }
#demo :where(p, div, span, li, h1, h2, h3, h4, td, th, blockquote, label, section, article, aside) { border:1px solid #4a7fb5; background:#eaf2fb; padding:6px 10px; margin:4px 0; border-radius:4px; }
#demo :where(ul, ol) { border:1px dashed #888; background:#fafafa; padding:8px 8px 8px 32px; margin:6px 0; }
#demo :where(table) { border-collapse:collapse; }
#demo :where(td, th) { border-radius:0; }
#demo :where(input, select, textarea) { margin:4px 0; }
</style>
</head>
<body>
<button id="resetBtn">Reset</button>
<section id="demo">
<style>.open { max-height:200px; transition: max-height 0.3s; }</style>
<div id="panel">Menu</div>
<button id="btn">Open</button>
</section>
<div id="output"></div>
<script>
var original = $("#demo").html();
function init() {
$("#btn").on("click", function() {
$("#panel").toggleClass("open");
});
}
init();
$("#resetBtn").click(function() {
$("#demo").html(original);
$("#output").empty();
init();
});
</script>
</body>
</html>
- Using
animate()for a simple hover or class change that a CSStransitionhandles more smoothly without JavaScript. - Setting a CSS
transitionon a property and also calling.animate()on it, so both run and fight each other. - Using CSS transitions and expecting a completion callback like animate's, when you must listen for the
transitionendevent instead.
Chapter Quiz — Complete all 9 topics to unlock
0/9 topics done
Complete these topics first: