React Portal Component: Creating Powerful and Flexible UI Renderings


React Portal is a powerful feature introduced in React 16 that allows developers to render components outside the normal DOM hierarchy. With React Portal, you can easily render components into a different part of the DOM, enabling you to build more flexible and sophisticated user interfaces. In this blog, we will explore React Portal component in detail, its use cases, benefits, and how it empowers developers to create UI renderings that were previously challenging or impossible to achieve.

Understanding React Portal

React Portal is a mechanism that facilitates rendering a child component into a different DOM node from its parent component. In the standard React rendering process, components are rendered within their parent's DOM hierarchy. However, there are scenarios where it is necessary to render a component at a different location in the DOM.

For instance, consider a modal dialog that needs to be rendered as a direct child of the <body> element, so it appears on top of other components and is not affected by the parent's styles or z-index. Prior to the introduction of React Portal, this was achieved using various techniques, such as manipulating the DOM directly or using libraries that handle portal-like behavior.

With React Portal, you can now achieve this without resorting to unconventional methods. It simplifies the process of rendering components outside of their parent's DOM hierarchy and improves code organization and maintainability.

How to Use React Portal?

Using React Portal is straightforward. To create a portal, follow these steps:

a) Create a Portal Container: First, define a new DOM element that will act as the container for the portal. This element should be outside the main root element of your React application. For example, you can create a <div> element with a specific ID, which will serve as the container.

// index.html
  <!-- Other HTML content -->
  <div id="modal-root"></div>

b) Implement the Portal: Within your React component, use the ReactDOM.createPortal method to render the child component into the portal container. This method takes two arguments: the child component to be rendered and the DOM node to serve as the portal container.

// Modal.js
import React from 'react';
import ReactDOM from 'react-dom';

const Modal = ({ children }) => {
  return ReactDOM.createPortal(
    <div className="modal">
export default Modal;

In this example, the Modal component is rendered into the #modal-root container, which is located outside the main root element of the React application.

c) Use the Portal Component: Now, you can use the Modal component anywhere in your application, and it will render its content into the portal container.

// App.js
import React from 'react';
import Modal from './Modal';

const App = () => {
  return (
      <h1>My App</h1>
        <p>This is a modal content.</p>
export default App;

Use Cases for React Portal

React Portals opens up a wide range of use cases, enabling developers to create advanced UI renderings and improve the user experience. Some common scenarios where React Portal proves invaluable include:

a) Modal Dialogs: As mentioned earlier, modal dialogs are a classic use case for portals. Modals need to be rendered outside the main application tree to ensure they appear on top of other elements and avoid any unintended side effects from the parent's styles or scroll behavior.

b) Tooltips and Popovers: When creating tooltips or popovers, you can use React Portal to render them in a separate container to ensure they don't affect the layout or styles of the parent components.

c) Contextual Menus: Context menus, especially those triggered by right-click events, benefit from being rendered outside the regular DOM hierarchy to allow for custom positioning and styling.

d) Portals for Global Components: In some cases, you may want to render a component at a specific location in the DOM, regardless of its position in the component tree. React Portal facilitates the creation of global components, such as a loading spinner or a toast notification, that can be triggered from anywhere in the application.

e) Avoiding Z-Index Issues: By rendering certain components as portals, you can avoid z-index issues that arise when components with different stacking contexts need to overlap each other.

Benefits of Using React Portal

React Portal provides numerous advantages that enhance the flexibility and maintainability of your React applications:

a) Improved Code Organization: With React Portal, you can keep portal-related components separate from the main component tree, resulting in cleaner and more organized code.

b) Simplicity and Elegance: Using React Portal simplifies the process of rendering components outside the normal DOM hierarchy, removing the need for unconventional techniques.

c) Preventing Side Effects: Portals help prevent side effects caused by rendering components with conflicting styles or event handlers within the same DOM tree.

d) Reusability: Portal components can be reused throughout the application, providing consistent behavior and appearance across different parts of the UI.

e) Enhanced User Experience: By enabling the creation of modal dialogs, tooltips, and other interactive UI elements, React Portal contributes to an improved and more user-friendly experience.

Performance Considerations

Although React Portal is a powerful feature, it's essential to consider its impact on performance. Since components rendered through portals exist outside the main component tree, React will treat them as separate trees and may need to perform additional reconciliations during updates.

However, in most cases, the impact on performance is negligible. React Portal is designed to be efficient and avoids unnecessary reconciliations by directly appending the portal component to its target container.

To further optimize performance when using React Portal:

a) Limit the Use of Portals: Only use portals when necessary, such as for modals or tooltips. Overusing portals can lead to unnecessary complexity and affect application performance.

b) Leverage React's Reconciliation: React's reconciliation process is highly efficient, and in many cases, the overhead of rendering through portals is negligible. Trust React to handle the rendering optimizations.

c) Minimize the Portal Tree: Keep the portal component tree as small as possible to minimize the number of elements that need to be appended to the portal container.

d) Avoid Frequent Updates: Minimize frequent updates to components rendered through portals to reduce the reconciliation overhead.


React Portal is a powerful feature that allows developers to render components outside the normal DOM hierarchy, offering enhanced flexibility and improved user experiences. With the ability to create modal dialogs, tooltips, and other interactive UI elements, React Portal empowers developers to build sophisticated user interfaces with ease.

By separating portal-related components from the main component tree, React Portal improves code organization and maintainability. It prevents side effects, optimizes performance, and ensures consistent behavior across different parts of the application.

As you explore React Portal, consider its use cases, benefits, and performance considerations. By leveraging this feature thoughtfully, you can create powerful and flexible UI renderings that enhance the user experience and elevate the overall quality of your React applications.

React Portal has become an invaluable tool for many developers, enabling them to overcome the limitations of the standard DOM rendering process and deliver impressive user interfaces with ease. As you continue to harness the capabilities of React Portal, you'll discover new opportunities to create cutting-edge and user-centric applications.

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