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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 cursor direction display emptyCells filter flex flexBasis flexDirection flexFlow flexGrow flexShrink flexWrap cssFloat 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

Web APIs

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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 length Property

Element Object


Find out how many <p> elements there are in the document:

var nodelist = document.getElementsByTagName("P").length;
Try it Yourself »

More "Try it Yourself" examples below.

Definition and Usage

The length property returns the number of nodes in a NodeList object.

A Node object's collection of child nodes is an example of a NodeList object.

The length property is useful when you want to loop through the nodes in a node list (See "More Examples" below).

This property is read-only.

Tip: Use the item() method to return a node at the specified index in a NodeList object.

Browser Support

length Yes Yes Yes Yes Yes



Technical Details

Return Value: A Number, representing the number of nodes in the nodelist
DOM Version Core Level 1 Nodelist Object

More Examples


Find out how many <p> elements there are inside a <div> element:

var div = document.getElementById("myDIV");           // Get the <div> element with id="myDIV"
var nodelist = div.getElementsByTagName("P").length;  // Get the number of <p> elements inside <div>
Try it Yourself »


Loop through all <p> elements inside a <div> element, and change the background color of each <p>:

var div = document.getElementById("myDIV");
var nodelist = div.getElementsByTagName("P");

var i;
for (i = 0; i < nodelist.length; i++) {
  nodelist[i].style.backgroundColor = "red";
Try it Yourself »


Return the number of child nodes of the <body> element:

var nodelist = document.body.childNodes.length;
Try it Yourself »


Loop through the child nodes of <body> and output the node name of each child node:

var nodelist = document.body.childNodes;

var txt = "";
var i;
for (i = 0; i < nodelist.length; i++) {
  txt = txt + nodelist[i].nodeName + "<br>";
Try it Yourself »

Related Pages

HTML DOM Reference: nodelist.item() Method

HTML DOM Reference: element.childNodes Property

HTML DOM Reference: element.getElementsByClassName() Method

HTML DOM Reference: element.getElementsByTagName() Method

HTML DOM Reference: element.querySelectorAll() Method

HTML DOM Reference: document.getElementsByClassName() Method

HTML DOM Reference: document.getElementsByName() Method

HTML DOM Reference: document.getElementsByTagName() Method

HTML DOM Reference: document.querySelectorAll() Method

Element Object