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useOptimistic – React's Guide to Enhancing User Experience

  • avatar
    Roy Bakker

In the realm of modern web development, optimizing user experiences in web applications is a priority. One powerful tool I often turn to is the useOptimistic React Hook. This feature lets developers update the UI in a responsive manner while asynchronous actions, like network requests, are in progress. This capability is critical for creating seamless interfaces that users appreciate.

By integrating useOptimistic with technologies like Next.js, TypeScript, and Node.js, I can harness its potential for enhancing real-world applications. For instance, when working with the latest Next.js 14 or React 19, this feature allows me to maintain fluidity and interactivity in the UI. Using useOptimistic in my code ensures I can build robust applications with rapid feedback and minimal downtime during updates, significantly improving the development workflow.


useOptimistic(state, updateFn)

The useOptimistic hook in React is useful when managing user interfaces that require immediate feedback during async actions, like API requests. This hook lets me display a different state while waiting for the server to respond, enhancing the user experience and making the interface more responsive.

Here’s a basic overview of its use:

import { useOptimistic } from 'react'

function AppContainer() {
  const [optimisticState, addOptimistic] = useOptimistic(state, (currentState, optimisticValue) => {
    // Combine current state and optimistic value
    return { ...currentState, ...optimisticValue }


  • state: The initial value to return when no action is in progress.
  • updateFn: A function that takes the current state and an optimistic value. It returns the new state by merging these values.


  • optimisticState: This represents the state during an ongoing action. If no action is pending, it returns the initial state.
  • addOptimistic: A function to trigger optimistic updates. It accepts an optimistic value, calls updateFn with the current state and this value, and returns the new optimistic state.

The hook enhances the user interface by reducing perceived latency. When a user triggers an action, the UI updates immediately to reflect the expected outcome, even if the operation is still in progress. This makes the app feel faster and more engaging. In practice, this technique can be used in features like liking a tweet or updating user profiles, where quick feedback is crucial.

By incorporating useOptimistic, developers can build more responsive and performant applications. This approach is especially valuable for complex interactions with databases or APIs, where waiting for a server response can otherwise slow down the interface.

Tables or lists can be used to structure this information for better clarity. This ensures that users have a responsive and seamless experience, making my app more efficient and user-friendly.

How to use the useOptimistic Hook

Fast Form Updates

I use the useOptimistic Hook to make my forms feel quicker. It allows the form to update right away without waiting for a network request to finish. When someone submits a form, like sending a message, the interface shows it immediately with a “Sending…” note.

Here is how it works:

  1. Form Submission: If a user sends a message, it shows up at once in the list with a "Sending…" status.
  2. Background Process: The form then tries to send this message to the server.
  3. Confirmation: When the server accepts the message, the “Sending…” note goes away, showing the message is sent.

This makes the app feel faster and more responsive, giving users a smooth and seamless experience even with possible network delays.