Useful for sharing information across a DOM tree

Usage no npm install needed!

<script type="module">
  import polymerIronMeta from 'https://cdn.skypack.dev/@polymer/iron-meta';


Published on NPM Build status Published on webcomponents.org


iron-meta is a generic element you can use for sharing information across the DOM tree.

See: Documentation, Demo.



npm install --save @polymer/iron-meta

In an HTML file

    <script type="module">
      import '@polymer/iron-meta/iron-meta.js';
    <iron-meta key="info" value="foo"></iron-meta>
    <!-- Other elements reading from the key 'info' see the value 'foo'. -->

In a Polymer 3 element

import {PolymerElement} from '@polymer/polymer/polymer-element.js';
import {html} from '@polymer/polymer/lib/utils/html-tag.js';

import '@polymer/iron-meta/iron-meta.js';

class ExampleElement extends PolymerElement {
  static get properties() {
    return {
      prop: String,

  static get template() {
    return html`
      <iron-meta key="info" value="{{prop}}"></iron-meta>
      info: [[prop]]

customElements.define('example-element', ExampleElement);


If you want to send a PR to this element, here are the instructions for running the tests and demo locally:


git clone https://github.com/PolymerElements/iron-meta
cd iron-meta
npm install
npm install -g polymer-cli

Running the demo locally

polymer serve --npm

Running the tests

polymer test --npm