The Difference Between Redux, Context & React Components in State Management

When building applications with React, there’s always a need to manage data that changes based on user interaction or from fetching external resources. React provides three primary methods to handle this kind of data: local component state, the Context API, and the Redux library. Each one fits a specific use case depending on the complexity and size of the app.

React Components – Managing Local State

In React, every component can manage its own local state using the useState hook. This local state model is ideal for simple scenarios that only involve a single component. For example, a button component that tracks how many times it’s been clicked can store that number internally:

function Counter() {
  const [count, setCount] = useState(0);

  return (
    <button onClick={() => setCount(count + 1)}>
      Button clicked {count} times
    </button>
  );
}

In the example above, the Counter component uses a count state value that is updated through the setCount function. Every time the button is clicked, React re-renders the component, which updates the displayed count.

This approach is simple and straightforward, making it easy to use. But it becomes less practical when multiple components need access to the same data. In such cases, data has to be passed down manually through component props. This practice is known as props drilling—passing props through multiple nested components—which can lead to messy code and difficulty in tracking data flow, especially in deep or large component trees.

React Context – Sharing State Across Components

When multiple components need access to the same piece of data, passing props manually through each intermediate component becomes inefficient. React’s built-in Context API solves this problem by allowing state to be shared across components without props drilling.

The Context API works by creating a Provider component that wraps around part (or all) of the component tree. This Provider holds a shared value that any nested component can consume using the useContext hook.

Context is commonly used for global-level values such as the current user, selected language, or theme preferences (like dark or light mode). To use Context effectively, follow these steps:

1. Create the Context: Use React.createContext() to create a new context object. You can optionally set a default value.
2. Wrap your app in a Provider: Use the context’s Provider to supply a value to all child components within its tree.
3. Consume the value: Any nested component can access the shared data using useContext(YourContext).

Here’s a simplified example that shares a theme value between two components:

const ThemeContext = createContext('light');

function App() {
  return (
    <ThemeContext.Provider value="dark">
      <Content />
    </ThemeContext.Provider>
  );
}

function Content() {
  const currentTheme = useContext(ThemeContext);
  return <p>Current theme: {currentTheme}</p>;
}

In this example, a context called ThemeContext is created with a default value of 'light'. The App component wraps its content with a ThemeContext.Provider, supplying the value 'dark'. Inside the Content component, useContext is used to access and display the current theme value.

Context makes it easy to share state across multiple components without passing props manually. However, it's important to note that when the context value changes, all components that consume it will re-render. This can impact performance if the data changes frequently or affects many components. For more complex scenarios or high-frequency updates, using Redux might provide better control and scalability.

Redux – Centralized State Management for Large Applications

Redux is a widely-used external library for managing state in JavaScript applications, including React. It provides a centralized approach where the entire application state is stored in a single object called the store. The state can only be modified by dispatching specific actions, which are handled by functions known as reducers.

The core concept of Redux is having a single source of truth—the global store. Any component can subscribe to specific parts of this state and dispatch actions to update it. By separating state update logic from the UI, Redux makes it easier to track and manage how data flows and changes across the app, especially with development tools like Redux DevTools.

For example, consider a complex app that involves user authentication, a shopping cart, settings, and other interconnected data. Redux helps organize and update all this state consistently. Today, the recommended way to use Redux with React is by using Redux Toolkit, a modern utility library that simplifies setup and provides cleaner APIs. One of its core features is createSlice, which allows you to define a specific piece of state and its logic in one place:

import { configureStore, createSlice } from '@reduxjs/toolkit';

const counterSlice = createSlice({
  name: 'counter',
  initialState: { value: 0 },
  reducers: {
    increment: (state) => { state.value += 1 },
    decrement: (state) => { state.value -= 1 }
  }
});

const store = configureStore({
  reducer: { counter: counterSlice.reducer }
});

In the code above, a slice called counter is created with an initial numeric value. It includes two reducers—increment and decrement—that define how the state should be updated. Redux Toolkit automatically generates corresponding action creators for these reducers. Then, the store is created using configureStore and passed the slice reducer.

To connect this store to a React app, wrap your root component in the Provider component from the react-redux library and pass the store to it, usually in index.js:

import { Provider } from 'react-redux';
import App from './App';
import store from './store';

root.render(
  <Provider store={store}>
    <App />
  </Provider>
);

Once connected, any component in the app can access the Redux state or dispatch actions to modify it. The react-redux library provides two hooks that simplify this process: useSelector for accessing state and useDispatch for sending actions. Here's a simple component that interacts with the counter state:

import { useSelector, useDispatch } from 'react-redux';
import { increment, decrement } from './counterSlice';

function CounterDisplay() {
  const count = useSelector((state) => state.counter.value);
  const dispatch = useDispatch();

  return (
    <div>
      <p>Count: {count}</p>
      <button onClick={() => dispatch(increment())}>Increase</button>
      <button onClick={() => dispatch(decrement())}>Decrease</button>
    </div>
  );
}

In this example, the CounterDisplay component uses useSelector to read the current count from the Redux store, and useDispatch to send actions when the buttons are clicked. The increment and decrement functions are action creators exported from the slice.

Redux provides several advantages that make state management in large-scale applications more structured and maintainable:

• It offers a unified and predictable structure for storing and updating data, which improves code clarity and maintainability.
• State changes are easy to trace using development tools like Redux DevTools, which show a step-by-step history of dispatched actions and state transitions.
• Redux follows the principle of immutable state, meaning state updates never modify the original object directly. Instead, they return a new state object. This minimizes bugs caused by unintended mutations.
• It supports asynchronous workflows (like API calls) very well using tools like createAsyncThunk in Redux Toolkit or middlewares such as redux-thunk. This makes handling loading, success, and error states much cleaner.
• It allows components to subscribe only to the specific parts of the state they care about (via useSelector), so only affected components re-render when that slice of state changes. This improves performance, especially in complex applications, compared to using Context alone.

Despite its power, Redux introduces an extra layer of complexity and boilerplate. For that reason, it's not recommended for small applications or when state management is simple. In those cases, using useState or Context is usually sufficient and keeps the codebase cleaner. Generally, Redux becomes truly valuable as the app grows and the state becomes more interconnected and demanding to manage.

Choosing the Right State Management Tool

• Local state with useState: Best suited for simple, self-contained data that belongs to a single component and doesn’t need to be shared.
• Context API: Ideal for sharing values like themes, language preferences, or user info across multiple components, especially when the data doesn’t change often.
• Redux: Well-suited for large or complex applications where multiple parts of the app depend on shared, frequently changing state. It offers better structure, debugging tools, and centralized control over how data flows and updates.

As a general rule, start simple. If local state (useState) meets your needs, use it. If you find yourself constantly passing props through multiple levels of components, consider switching to Context. And when the application becomes too complex to manage with either of those tools—such as when you need centralized logic, action tracking, or async state control—then Redux is the better option.

State management in React is a critical part of building interactive applications. React offers different tools—from built-in solutions like useState and Context to advanced external libraries like Redux. Each tool has its own strengths and limitations. The key is to understand the specific requirements of your application and choose the approach that balances simplicity, scalability, and maintainability. With the right strategy in place, it’s possible to build robust, performant React applications with well-organized and predictable state logic.