What is React Query? A modern approach to data management in React applications

In this article, we will take a closer look at what React Query really is, why it has gained immense popularity in the React community, and how it can transform everyday work on web applications. If you are looking for a modern, flexible and efficient way to manage server data – you are in the right place.

What is React Query?

React Query is a modern open source library designed to manage server-side data in React-based applications. Its main goal is to simplify the process of communicating with external data sources – such as REST APIs or GraphQL – and to eliminate repetitive code that becomes cumbersome and error-prone in the traditional approach.

React Query is not another library for global application state, such as Redux or Zustand. Instead, it focuses exclusively on the state of asynchronous data, i.e. the data we retrieve from the server. In this regard, it offers complete, turnkey solutions for:

• data retrieval (useQuery),
• data saving and updating (useMutation),
• automatic caching and synchronization,
• loading state management, error and success handling.

The library was created by Tanner Linsley and developed as part of the TanStack project, which is also responsible for other popular frontend tools such as TanStack Table and TanStack Router. It is worth mentioning that since version 4, the library formerly known as React Query has been officially renamed TanStack Query. This change is due to the standardization of the naming of all tools created by the TanStack team (including TanStack Table and TanStack Router). Although the package is still called @tanstack/react-query, it is worth being aware of this change, especially when working with documentation and newer versions of the library.

Thanks to its declarative approach, developers do not have to manually manage many aspects of HTTP query logic – everything is managed behind the scenes by React Query. This makes the code more transparent, less prone to errors, and much easier to maintain, especially in large and complex projects.

In short, React Query is the missing piece of React when it comes to server communication.

What are the key features of React Query?

React Query has gained great recognition among developers thanks to its well-thought-out set of features that significantly simplify and streamline work with external data. Below are the most important capabilities that make this library an almost indispensable tool in modern React applications:

1. Declarative data retrieval (useQuery)

Instead of manually managing the HTTP query lifecycle, loading and error states, React Query allows you to define the query in a declarative way. Hook useQuery automatically handles data retrieval, storage and UI updates depending on the state of the query.

Example:

const { data, isLoading, error } = useQuery(['users'], fetchUsers);

2. Automatic data caching

The data retrieved from the API is automatically stored in a cache. If the same query is executed again, React Query can use the data from the cache without resending the request – speeding up the application and reducing network load.

3. Background synchronization

React Query can automatically refresh the data in the background when a component is re-installed or the user returns to bookmark the application. This keeps the data up to date without the user having to manually refresh the interface.

4. Support pagination and infinite scrolling

Thanks to hooks such as useInfiniteQuery, the library offers support for more complex scenarios, such as pagination of data or loading more records when scrolling. What’s more, it allows you to retain data from previous pages, resulting in better UX.

5. Intelligent query state management

React Query automatically manages various query states – from isLoading, to isFetching, to isError and isSuccess. This makes it easy to create a dynamic UI that responds to the current state of API communication without having to write your own logic.

6. Mutations (useMutation) and optimistic updates

Hook useMutation allows you to perform write operations (POST, PUT, DELETE) and handle their progress – from start to success to errors. In addition, the library supports optimistic updates, that is, immediate changes to the UI before the server confirms their execution, which improves the smoothness and responsiveness of the application.

7. Debugging with React Query Devtools

React Query also offers a developer tool – React Query Devtools, which shows the real-time status of all queries and mutations in the application. This is invaluable support when creating and debugging more complex data logics.

Why use React Query?

React Query is a tool that gives you a real advantage in both your daily work and long-term application development. It eliminates unnecessary complexity, allowing frontend developers to focus on what really matters – creating modern, fast, and stable interfaces. React Query is more than just a library – it’s an approach that changes the way you think about data management in React applications. It enables you to create more stable, predictable, and efficient communication systems with APIs. Here are the most important reasons why you should use it:

Less boilerplate – less code to manage state

Instead of writing useEffect, useState, try/catch, finally, manually cleaning up effects, refreshing components, and other query handling mechanisms every time, React Query reduces all this logic to a single declarative function. The code becomes cleaner, more concise, and much easier to maintain, especially in larger teams.

Better performance – queries are cached, data is not fetched unnecessarily

React Query automatically stores data in a cache. If the same data is needed again – e.g., when switching between tabs or returning to a page – it can be used from the cache without another HTTP request. This significantly speeds up the application and reduces the number of unnecessary connections to the server.

The developer also has control over how long data remains “fresh,” when it expires, and whether it should be refetched in the background.

Reactivity – components update automatically when data changes

In React Query, data is “live.” When a mutation updates data on the server, the corresponding queries can be automatically refreshed, so that the components presenting that data receive new values without manual intervention.

There is no need to write your own mechanisms to synchronize the UI with the backend. React Query makes sure that the user always sees the latest information.

Extensibility – ready for larger projects

React Query offers tremendous flexibility. You can easily customize query behavior to suit your application’s needs: set retry rules for errors, delay refetching, combine data from different sources, and even create custom caching strategies.

What’s more, thanks to Devtools, we can monitor the status of all queries and mutations in real time, which is invaluable in team projects and production environments.

Example of basic use of React Query

No complicated configuration is required to start using React Query. The library has been designed to make implementation in an existing project as quick and intuitive as possible. Below you will find step-by-step instructions on how to run React Query and retrieve your first data.

Installing the library

We start by installing the package:

npm install @tanstack/react-query

You can also use yarn, if that’s your preferred package manager. Additionally, it’s a good idea to install React Query Devtools, especially at the development stage:

npm install @tanstack/react-query-devtools

Configuration QueryClient and QueryClientProvider

Before you can use hooks such as useQuery, you need to configure a query client and make it available to the entire application through the context. This is usually done in the main file, such as App.tsx or main.tsx:

import { QueryClient, QueryClientProvider } from '@tanstack/react-query';

const queryClient = new QueryClient();

function App() {
  return (
    <QueryClientProvider client={queryClient}>
      <MyComponent />
    </QueryClientProvider>
  );
}

This ensures that every component in the React tree has access to the React Query context and can use its functions.

Retrieving data with useQuery

Now we can create a component that retrieves data from the API. Most often it looks like this:

import { useQuery } from '@tanstack/react-query';

async function fetchUsers() {
  const response = await fetch('https://jsonplaceholder.typicode.com/users');
  if (!response.ok) throw new Error('Error data processing');
  return response.json();
}

function UsersList() {
  const { data, isLoading, error } = useQuery(['users'], fetchUsers);

  if (isLoading) return <p>Ładowanie...</p>;
  if (error) return <p>An error occurred</p>;

  return (
    <ul>
      {data.map(user => (
        <li key={user.id}>{user.name}</li>
      ))}
    </ul>
  );
}

Note a few things:
– The useQuery hook takes a unique key (['users']) and a function that fetches data.
– React Query automatically manages the isLoading and error states.
– Once the data is available, the list of users is rendered.

Saving data using useMutation

Just like useQuery simplifies data fetching, useMutation allows you to handle data modifications—such as adding a new user—in a declarative and efficient way.

Below is an example of a component that lets you add a new user to a list:

import { useMutation, useQueryClient } from '@tanstack/react-query';

async function addUser(newUser) {
  const response = await fetch('https://jsonplaceholder.typicode.com/users', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify(newUser),
  });
  if (!response.ok) throw new Error('Error while adding user');
  return response.json();
}

function AddUserForm() {
  const queryClient = useQueryClient();

  const mutation = useMutation({
    mutationFn: addUser,
    onSuccess: () => {
      // Invalidate the 'users' query so it gets refetched automatically
      queryClient.invalidateQueries(['users']);
    },
  });

  const handleSubmit = (e) => {
    e.preventDefault();
    const formData = new FormData(e.target);
    const name = formData.get('name');
    mutation.mutate({ name });
  };

  return (
    <form onSubmit={handleSubmit}>
      <input type="text" name="name" placeholder="User name" required />
      <button type="submit" disabled={mutation.isPending}>
        Add User
      </button>

      {mutation.isPending && <p>Adding user...</p>}
      {mutation.isError && <p>Error: {mutation.error.message}</p>}
      {mutation.isSuccess && <p>User added successfully!</p>}
    </form>
  );
}

A few key points to notice:
– useMutation handles all states of the request (loading, error, success) in a declarative way.
– On success, the ['users'] query is invalidated, prompting React Query to refetch the latest data automatically.
– The component is simple and clean—no manual refetching or local state logic is needed to sync the UI with the server.

Why is this approach better?

Unlike traditional useEffect and useState, you don’t need to create additional state variables, control when the fetch is executed, or keep track of cleaning up effects. React Query does it for you, giving you a simple interface with full control over your data.

This is a very basic example, but it shows the power and convenience of using this library from the very first use. In the following points, you can extend this approach with mutations, pagination, and background data refresh.

What are the advanced features of Tanstack-Query?

React Query offers much more than just basic data retrieval. As your application grows and becomes more dynamic, these features make a huge difference.

StubsTime and CacheTime

With these settings, you control how long data stays fresh and when it can be removed from the cache. This gives you precise control over the data lifecycle and reduces unnecessary queries.

Data refetching

You can automatically refresh data when the user returns to the card, when the component is remounted, or at specified intervals. This is especially useful in applications where data changes frequently and must always be up to date.

Query invalidation

After performing a mutation, such as adding a new item to a list, you can specify specific queries that should be marked as obsolete. React Query will automatically refresh them – without the need to manually trigger additional fetches. This eliminates data inconsistency issues between the frontend and backend that often occur when working with a classic API approach. Additionally, you have granular control over what, when, and how it should be refreshed.

Data prefetching

You can fetch data “in advance” before the user navigates to a given view. This significantly speeds up the loading of subpages and improves the smoothness of the application.

Data transformation and custom functions

React Query allows you to modify data before it reaches the component. With the selectoption, you can, for example, transform the API response, filter an array, or change the structure of an object. Combined with custom queryFnfunctions, this gives you tremendous flexibility and allows you to tailor everything to the needs of the UI without rewriting data in the component itself.

Devtools

React Query Devtools is a convenient debugging tool. It shows the cache status, active queries, their statuses, and operation history. It is ideal for diagnosing problems and optimizing applications, especially in a team environment.

When not to use React Query?

Although React Query is a powerful tool that solves many data retrieval problems, it will not always be the best choice. In some cases, its implementation may be excessive – both technically and organizationally.

If your application does not communicate with any API and all data is static or stored locally, using React Query simply does not make sense. Examples include small information applications, single offline forms, or static pages.

Similarly, in projects with minimal asynchronous logic, where data is retrieved only once and does not change, you can successfully stick with the classic useEffect. In such a scenario, an additional layer of abstraction in the form of React Query will not bring any real benefits.

It is also worth considering the level of expertise of your team. React Query requires an understanding of new concepts such as invalidation, cache time, background refetching, and mutations. For beginners, this can be an unnecessary barrier to entry, especially if they have not yet mastered the basics of working with data in React.

There are also situations where you need full control over the entire data flow – for example, in very complex authentication scenarios, non-standard retry logic, or interactions that depend on global state. In such cases, writing your own solutions may be more flexible and readable than adapting to the React Query architecture.

In summary, you should not use React Query in:

– very simple projects where data is fetched once and does not require synchronization or state management
– applications that do not use data from an external source (e.g., a server or API)

When to choose React Query over Redux?

React Query is worth choosing when your application communicates intensively with the API and you need efficient management of asynchronous data – such as list fetching, details, mutations or background synchronisation. Unlike Redux, which does a better job of managing UI state and global application logic, React Query automatically handles caching, updates and refetching, significantly reducing code and increasing performance. If your main challenge is working with server data rather than building complex application state – React Query will be a better choice.

Summary

React Query is a modern and extremely practical tool that significantly simplifies working with server-side data in React applications. With its declarative approach, automatic caching, background synchronization, and rich set of configuration options, it allows you to eliminate repetitive code, increase application performance, and improve the quality of the entire frontend. For teams working on dynamic applications that frequently communicate with APIs, React Query can become a key element of the architecture. It not only speeds up development, but also reduces the number of errors and facilitates data lifecycle management.

However, it is worth remembering that not every application requires such an advanced approach. In simpler projects, where data is static or limited to a single download, using React Query may be overkill.

To sum up: if you are building an application where data from the server plays a key role, React Query is a tool that is definitely worth learning and implementing. It is an investment that pays off very quickly – in the form of cleaner code, better UX, and peace of mind during project development.

Frequently asked questions (FAQ)

Does React Query work with React Native?

Yes. React Query works in both React and React Native applications because it is based on React hooks. In a mobile environment, you can simply use fetch or Axios, just like in a web application.

Does React Query work with Next.js and SSR?

Yes. React Query supports server-side rendering (SSR) with Next.js. With features such as dehydrate and Hydrate, you can pass data fetched on the server to the client, avoiding double fetching.

Can React Query be used with GraphQL?

Yes. React Query is not limited to REST APIs. It can also be used with GraphQL, as long as the queryFn function returns a Promise. It does not offer native integration with GraphQL, but it gives you full control over data fetching.

How is React Query different from Redux?

Redux is a tool for managing the global state of an application, while React Query focuses exclusively on asynchronous data fetched from the server. React Query automatically caches data, handles loading and errors, without the need to define actions, reducers or middleware.

Do I need Zustand or Recoil together with React Query?

No, if you only need data from the API. Zustand and Recoil are better suited for managing UI state, while React Query is used for managing asynchronous data. You can combine them if your project requires it.

How do I test components with React Query?

For testing, it’s best to use @testing-library/react and msw (Mock Service Worker) for mocking queries. Remember to wrap the component you’re testing in QueryClientProvider so that React Query works correctly in tests.