How useDeferredValue Can Improve React App Responsiveness

React introduced useDeferredValue in version 18 as part of its concurrent rendering capabilities. While it's not as well known as useTransition, it’s a powerful hook that can help you improve perceived performance by deferring non-urgent updates.

Let’s break it down.

What is useDeferredValue?

useDeferredValue lets you tell React: “This value can wait.”

It’s useful when you want to update a component immediately with some state, but postpone rendering heavier parts of the UI that depend on that value — like search results, large lists, or charts.

A Practical Example

Imagine you're building a search input:

const [query, setQuery] = useState("");
const deferredQuery = useDeferredValue(query);
const results = useSearch(deferredQuery);

Here’s what happens:

The input updates immediately as the user types (query).
But the actual search (useSearch) only re-runs after the input settles.
React keeps showing the previous results for a short time, reducing flicker and improving responsiveness.

This feels much faster to the user — especially if the results list is expensive to render.

When to Use It

✅ Use it when:

You have fast-changing state (like text input).
Some parts of the UI are slow to update.
You want to keep the interface snappy.

❌ Avoid it when:

All UI updates are lightweight.
You need real-time updates (e.g., form validation).

useDeferredValue vs useTransition

Both let you control update priority — but in different ways:

useTransition wraps a state update and marks it as low-priority.
useDeferredValue marks a value as low-priority.

Think of useTransition as saying, “update this later,” and useDeferredValue as “react to this value later.”

You can try a working example here: React useDeferredValue demo on CodeSandbox

Final Thoughts

useDeferredValue is a small but powerful tool in the React 18 toolbox. It won’t magically speed up your app — but it can dramatically improve how fast it feels.

Have you used it in production? Let’s connect and exchange ideas.

Written by Gil, a fullstack developer with 15+ years of experience, passionate about practical architecture, clean UX, and blockchain-powered applications.