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align-content align-items align-self all animation animation-delay animation-direction animation-duration animation-fill-mode animation-iteration-count animation-name animation-play-state animation-timing-function backface-visibility background background-attachment background-blend-mode background-clip background-color background-image background-origin background-position background-repeat background-size border border-bottom border-bottom-color border-bottom-left-radius border-bottom-right-radius border-bottom-style border-bottom-width border-collapse border-color border-image border-image-outset border-image-repeat border-image-slice border-image-source border-image-width border-left border-left-color border-left-style border-left-width border-radius border-right border-right-color border-right-style border-right-width border-spacing border-style border-top border-top-color border-top-left-radius border-top-right-radius border-top-style border-top-width border-width bottom box-shadow box-sizing caption-side clear clip color column-count column-fill column-gap column-rule column-rule-color column-rule-style column-rule-width column-span column-width columns content counter-increment counter-reset cursor direction display empty-cells filter flex flex-basis flex-direction flex-flow flex-grow flex-shrink flex-wrap float font @font-face font-family font-size font-size-adjust font-stretch font-style font-variant font-weight hanging-punctuation height justify-content @keyframes left letter-spacing line-height list-style list-style-image list-style-position list-style-type margin margin-bottom margin-left margin-right margin-top max-height max-width @media min-height min-width nav-down nav-index nav-left nav-right nav-up opacity order outline outline-color outline-offset outline-style outline-width overflow overflow-x overflow-y padding padding-bottom padding-left padding-right padding-top page-break-after page-break-before page-break-inside perspective perspective-origin position quotes resize right tab-size table-layout text-align text-align-last text-decoration text-decoration-color text-decoration-line text-decoration-style text-indent text-justify text-overflow text-shadow text-transform top transform transform-origin transform-style transition transition-delay transition-duration transition-property transition-timing-function unicode-bidi vertical-align visibility white-space width word-break word-spacing word-wrap z-index


CSS3 opacity Property


Set the opacity level for a <div> element:

div {
    opacity: 0.5;
Try it yourself »

More "Try it Yourself" examples below.

Definition and Usage

The opacity property sets the opacity level for an element.

The opacity-level describes the transparency-level, where 1 is not transparent at all, 0.5 is 50% see-through, and 0 is completely transparent.

Default value: 1
Inherited: no
Animatable: yes, see individual properties. Read about animatable Try it
Version: CSS3
JavaScript syntax: object.style.opacity="0.5" Try it

Browser Support

The numbers in the table specify the first browser version that fully supports the property.

opacity 4.0 12.0 9.0 2.0 3.1 9.0

Note: IE8 and earlier versions supports an alternative, the filter property. Like: filter:Alpha(opacity=50).

CSS Syntax

opacity: number|initial|inherit;

Property Values

Value Description Play it
number Specifies the opacity. From 0.0 (fully transparent) to 1.0 (fully opaque) Play it »
initial Sets this property to its default value. Read about initial Play it »
inherit Inherits this property from its parent element. Read about inherit


More Examples


How to use JavaScript to change the opacity for an element:

function myFunction(x) {
// Return the text of the selected option
    var opacity = x.options[x.selectedIndex].text;
    var el = document.getElementById("p1");
    if (el.style.opacity !== undefined) {
        el.style.opacity = opacity;
    } else {
        alert("Your browser doesn't support this example!");
Try it yourself »

Related Pages

CSS tutorial: CSS Image Opacity / Transparency

HTML DOM reference: opacity property