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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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Other References

CSSStyleDeclaration JS Conversion


HTML DOM Element getElementsByClassName()

Examples

Change the text of the first list item with class="child":

const list = document.getElementsByClassName("example")[0];
list.getElementsByClassName("child")[0].innerHTML = "Milk";
Try it Yourself »

Number of elements with class="child" in "myDIV":

const element = document.getElementById("myDIV");
const nodes = element.getElementsByClassName("child");
let number = nodes.length;
Try it Yourself »

Change the size of the second element with class="child":

const element = document.getElementById("myDIV");
element.getElementsByClassName("child")[1].style.fontSize = 24px";
Try it Yourself »

More examples below.


Definition and Usage

The getElementsByClassName() method returns a collection of child elements with a given class name.

The getElementsByClassName() method returns a NodeList object.


NodeList

A NodeList is an array-like collection (list) of nodes.

The nodes in the list can be accessed by index. The index starts at 0.

The length Poperty returns the number of nodes in the list.


Syntax

element.getElementsByClassName(classname)

Parameters

Parameter Description
classname Required.
The class name of the child elements.
Separate multiple names with spaces ("child color").

Return Value

Type Description
NodeListThe elements' child elements with the given class name.
The elements are sorted as they appear in the source code.


More Examples

Change the size of the first element with "child" and "color" classes inside the second element with class="example":

const elements = document.getElementsByClassName("example")[1];
elements.getElementsByClassName("child color")[0].style.fontSize = "24px";
Try it Yourself »

Change the color of all elements in "myDIV" with class="child":

const element = document.getElementById("myDIV");
const nodes = element.getElementsByClassName("child");
for (let i = 0; i < nodes.length; i++) {
  nodes[i].style.color = "red";
}
Try it Yourself »

Browser Support

element.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