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alignContent alignItems alignSelf animation animationDelay animationDirection animationDuration animationFillMode animationIterationCount animationName animationTimingFunction animationPlayState background backgroundAttachment backgroundColor backgroundImage backgroundPosition backgroundRepeat backgroundClip backgroundOrigin backgroundSize backfaceVisibility border borderBottom borderBottomColor borderBottomLeftRadius borderBottomRightRadius borderBottomStyle borderBottomWidth borderCollapse borderColor borderImage borderImageOutset borderImageRepeat borderImageSlice borderImageSource borderImageWidth borderLeft borderLeftColor borderLeftStyle borderLeftWidth borderRadius borderRight borderRightColor borderRightStyle borderRightWidth borderSpacing borderStyle borderTop borderTopColor borderTopLeftRadius borderTopRightRadius borderTopStyle borderTopWidth borderWidth bottom boxShadow boxSizing captionSide caretColor clear clip color columnCount columnFill columnGap columnRule columnRuleColor columnRuleStyle columnRuleWidth columns columnSpan columnWidth counterIncrement counterReset cssFloat cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap font fontFamily fontSize fontStyle fontVariant fontWeight fontSizeAdjust height isolation justifyContent left letterSpacing lineHeight listStyle listStyleImage listStylePosition listStyleType margin marginBottom marginLeft marginRight marginTop maxHeight maxWidth minHeight minWidth objectFit objectPosition opacity order orphans outline outlineColor outlineOffset outlineStyle outlineWidth overflow overflowX overflowY padding paddingBottom paddingLeft paddingRight paddingTop pageBreakAfter pageBreakBefore pageBreakInside perspective perspectiveOrigin position quotes resize right scrollBehavior tableLayout tabSize textAlign textAlignLast textDecoration textDecorationColor textDecorationLine textDecorationStyle textIndent textOverflow textShadow textTransform top transform transformOrigin transformStyle transition transitionProperty transitionDuration transitionTimingFunction transitionDelay unicodeBidi userSelect verticalAlign visibility width wordBreak wordSpacing wordWrap widows zIndex

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HTML Objects

<a> <abbr> <address> <area> <article> <aside> <audio> <b> <base> <bdo> <blockquote> <body> <br> <button> <canvas> <caption> <cite> <code> <col> <colgroup> <datalist> <dd> <del> <details> <dfn> <dialog> <div> <dl> <dt> <em> <embed> <fieldset> <figcaption> <figure> <footer> <form> <head> <header> <h1> - <h6> <hr> <html> <i> <iframe> <img> <ins> <input> button <input> checkbox <input> color <input> date <input> datetime <input> datetime-local <input> email <input> file <input> hidden <input> image <input> month <input> number <input> password <input> radio <input> range <input> reset <input> search <input> submit <input> text <input> time <input> url <input> week <kbd> <label> <legend> <li> <link> <map> <mark> <menu> <menuitem> <meta> <meter> <nav> <object> <ol> <optgroup> <option> <output> <p> <param> <pre> <progress> <q> <s> <samp> <script> <section> <select> <small> <source> <span> <strong> <style> <sub> <summary> <sup> <table> <tbody> <td> <tfoot> <th> <thead> <tr> <textarea> <time> <title> <track> <u> <ul> <var> <video>

Other References

CSSStyleDeclaration JS Conversion


HTML DOM Document getElementsByClassName()

Example

Get all elements with class="example":

const collection = document.getElementsByClassName("example");
Try it Yourself »

Get all elements with both the "example" and "color" classes:

const collection = document.getElementsByClassName("example color");
Try it Yourself »

More examples below.


Definition and Usage

The getElementsByClassName() method returns a collection of elements with a specified class name(s).

The getElementsByClassName() method returns an HTMLCollection.

The getElementsByClassName() property is read-only.


HTMLCollection

An HTMLCollection is an array-like collection (list) of HTML elements.

The elements in a collection can be accessed by index (starts at 0).

The length Property returns the number of elements in the collection.



Syntax

document.getElementsByClassName(classname)

Parameters

Parameter Description
classname Required.
The class name of the elements.
Search for multiple class names separated by spaces like "test demo".

Return Value

Type Description
Object.An HTMLCollection object.
A collection of elements with the specified class name.
The elements are sorted as they appear in the document.


More Examples

Number of elements with class="example":

let numb = document.getElementsByClassName("example").length;
Try it Yourself »

Change the background color of all elements with class="example":

const collection = document.getElementsByClassName("example");
for (let i = 0; i < collection.length; i++) {
  collection[i].style.backgroundColor = "red";
}
Try it Yourself »

Related Pages

CSS Tutorial: CSS Syntax

CSS Reference: CSS .class Selector

HTML DOM Reference: element.getElementsByClassName()

HTML DOM Reference: className Property

HTML DOM Reference: classList Property

HTML DOM Reference: Style Object


Browser Support

document.getElementsByClassName() is a DOM Level 1 (1998) feature.

It is fully supported in all browsers:

Chrome IE Edge Firefox Safari Opera
Yes 9-11 Yes Yes Yes Yes