Svelte vs. React: A Head-to-Head Comparison for 2024

There’s so much innovation happening in the web development sphere nowadays. With the current diversity of JavaScript frameworks and libraries, it can be pretty daunting to pick the one to use for the project. Among the top choices are React, a long-established leader in UI development, and Svelte, a newer contender known for its simplicity and performance. 

Both offer unique advantages for building dynamic applications and addressing common developer problems. So, if you are trying to decide between React development and exploring Svelte for your next project, we’ve got you covered. In this article, we’ll compare Svelte vs. React, breaking down their features, strengths, and weaknesses. 

Let’s start with React. 

Overview of React

React is a well-known open-source JavaScript library for building dynamic and responsive user interfaces. It was developed by Jordan Walke, a software engineer at Meta (formerly Facebook), and first released in 2013. Meta initially used it to improve their news feed, and it later became open-source, making the library available for everyone to use.

Today, it’s one of the most widely used tools in web development. React is maintained by Meta and is supported by a vast developer community worldwide. It focuses on creating reusable components — self-contained pieces of UI code — making development more efficient and scalable.

React’s primary goal is to provide developers with a fast and flexible way to build interactive web applications where parts of the interface can change without reloading the entire page. For example, on an online shopping site, React can make the cart update instantly when you add or remove an item without reloading the page.

Other distinctive features of React include:

• Components. React applications are built using components, which are like reusable building blocks of UI. Each component represents a part of the interface and encapsulates its own logic, styling, and behavior.
• JSX. JSX is a syntax extension that allows you to write HTML-like code within JavaScript and makes it easier to understand.
• Virtual DOM. The Virtual DOM is React’s way of optimizing UI updates. Instead of interacting directly with the browser’s DOM (which is rather slow), React uses a lightweight copy of the DOM called the Virtual DOM. When the app’s state changes, React updates the Virtual DOM. It compares the new version with the previous one and calculates the minimum changes, which are then applied to the real DOM.
• Declarative nature. React is declarative, meaning you describe what you want the UI to look like, and React figures out how to make it happen.
• One-way data binding. In React, data flows in one direction, from a parent component to its child components. This makes it easier to understand how data is being passed and updated.
• React hooks. Hooks were introduced in React 16.8 and allow developers to use features like state and lifecycle methods in functional components.

Pros and cons of React

React, like any technology, has its advantages and disadvantages. The pros include:

• Community support. React has a vast and active community. Therefore, developers have access to a wealth of libraries, tutorials, forums, and tools, making it easier to solve issues.
• Rich set of libraries and tools. As we mentioned, React’s ecosystem has been well-established over the years, with a wide array of libraries for routing, state management, form handling, and more.
• Reusable components. React’s component-based design helps developers reuse components. This saves time and effort. They can build a library of components to use in different projects. This method keeps things consistent and lowers the chances of bugs.
• Performance optimization. With the Virtual DOM and efficient diffing algorithms, React optimizes rendering and ensures that applications run smoothly, even with large datasets or complex interfaces.

React cons include:

• Larger bundle size. The virtual DOM and additional third-party libraries in React applications often contribute to larger bundle sizes. While it’s insignificant for large applications, it can be critical for small or medium-sized apps with limited resources or focus on speed.
• Poor documentation. One of the main issues is that the documentation often struggles to keep up with the frequent updates released for the library. This can make it challenging for developers, especially those new to React, to find accurate and up-to-date information when needed.
• Requires more boilerplate code. While React is powerful by itself, it’s not a full-fledged framework but a library, and its primary focus is building UI. Therefore, it often requires additional libraries and configuration to handle routing, state management, and other essential features. This can lead to more boilerplate code, increasing the complexity of the setup.
• Steep learning curve. While JSX offers a simpler, more readable syntax by combining HTML-like code with JavaScript, new developers may initially find it challenging. However, with time and effort, the benefits make it worth mastering.

Overview of Svelte

Svelte is a free, open-source JavaScript-based web framework developed by Rich Harris in 2016. It evolved from Harris’s earlier work on Ractive.js, a UI library designed for creating highly dynamic web applications, which was released in 2013. Harris developed Svelte with the goal of simplifying web development, making it more accessible for a broader audience by providing an intuitive and efficient way to build rich, interactive web applications. 

Svelte is unique in its performance optimization. It uses a compiler to convert HTML templates into vanilla JavaScript, resulting in smaller app bundles.

However, Svelte is not only a framework with compiler functionality, but it also introduces a specialized syntax for describing user interfaces. This syntax is tightly integrated with HTML, CSS, and JavaScript, making it feel distinct while still relying on standard web technologies. Through its compiler, Svelte transforms this syntax into highly optimized JavaScript code that directly manipulates the DOM.

Key features of Svelte include:  

• Reactive. Svelte has built-in reactivity, meaning you don’t need to manage the state manually with hooks or external libraries. It updates the DOM automatically during build time.
• Plain and simple. If you know HTML, CSS, and JavaScript, consider that you know Svelte as well since it’s really easy to learn. 
• Lightweight and less code. Building features and functions in Svelte requires minimal coding. A few lines of code are often enough to perform the task.
• Scoped styles. Svelte encapsulates CSS within components, so styles written in a Svelte file apply only to that component. This ensures that styles in one component won’t unintentionally affect other parts of your application.

Pros and cons of Svelte

As with React, Svelte also has its benefits and drawbacks. The pros include:

• Small bundle size. Svelte compiles only the code needed for a specific component, resulting in smaller bundle sizes than React or Angular, which include runtime libraries. Smaller bundles improve initial load times, especially for users with slower networks or devices.
• No virtual DOM. Svelte does not use a virtual DOM. Instead, it turns code into optimized JavaScript and updates the real DOM directly when the application’s state changes. This means the app uses less memory and runs faster.
• Easy to learn. Svelte is less verbose and easier to learn than other frameworks. Its syntax is clean and intuitive, requiring less boilerplate code. 

Svelte cons are:

• Smaller community. Even though Svelte’s community is growing, it remains smaller than older frameworks and libraries like React or Angular. Developers may find fewer ready-made libraries and plugins for specific use cases.
• Less mature ecosystem. Svelte’s ecosystem is still evolving, meaning fewer tools, tutorials, and third-party integrations are available compared to older frameworks.
• Limited corporate adoption. While Svelte is growing in popularity, it is not as widely adopted in the industry as React or Vue, which can limit job opportunities and community support.
• Learning curve for those familiar with other frameworks. Svelte is often considered easier for beginners because of its straightforward syntax and less boilerplate code. However, developers who are already familiar with other frameworks like React or Angular can experience a learning curve when switching to Svelte.

Similarities between Svelte and React

As Svelte and React are both JavaScript-based tools, it’s not surprising they share some common features. So, before we compare their differences, let’s see what similarities they have. 

• Component-based architecture. Both Svelte and React use a component-based approach, allowing developers to create reusable pieces of UI. Svelte components have a .svelte extension, while React uses .jsx.
• Reactivity. Reactivity ensures the UI updates automatically when data changes. React achieves this with state and props, requiring explicit updates. Svelte simplifies it with reactive variables, which update automatically with minimal code.
• JSX-like syntax. Both frameworks let you write HTML-like code in JavaScript. React uses JSX, while Svelte has its own syntax, which is similar in style but unique for the framework.
• Server-side rendering and code splitting. React has Next.js for features like server-side rendering and code splitting. Svelte offers similar functionality with SvelteKit.
• Open-source community. Both Svelte and React have active and thriving open-source communities that contribute to their growth and ecosystem.

Svelte vs. React: key differences

While both Svelte and React serve the same purpose — building user interfaces — they do so in fundamentally different ways. Therefore, let’s take a closer look at their differences.

Performance

Performance is really important for any frontend framework because it affects how fast and smooth your app feels to users. Svelte and React handle performance in different ways.

As mentioned earlier, React uses a virtual DOM, which is like a temporary in-memory copy of the actual DOM (the real webpage). When a React component’s state or props change, it first updates the virtual DOM, which then compares the updated virtual DOM with its previous version. This process, known as “reconciliation,” determines the minimal set of changes needed to update the real DOM efficiently. By batching and minimizing these updates, React avoids unnecessary DOM manipulations, making it faster and more efficient than directly interacting with the DOM using plain JavaScript.

However, the virtual DOM still introduces some computational overhead, as React must constantly compare and reconcile the virtual and real DOM. This can sometimes slow down application performance with frequent, complex updates, especially if not optimized carefully.

Svelte, however, works differently. It bypasses the virtual DOM by compiling code into highly optimized JavaScript that directly updates the DOM. This approach leads to faster startup times and enhances runtime performance, creating a smoother, more responsive experience for users.

State management

Managing the application state is a critical consideration in building modern web apps. Effective state management ensures that the UI reflects the current state of the application and responds appropriately to user interactions. 

React uses hooks like useState and useReducer for local state management. For global state management often employed libraries like Redux, MobX, or React Context. While these tools are powerful, they can add complexity to the development process.

Svelte simplifies state management by offering built-in reactivity. Variables in Svelte components are reactive by default, and you can use stores for shared state with minimal setup. This makes it easy to manage state without relying on third-party libraries.

Bundle size

Svelte applications typically have smaller bundle sizes compared to React. Since Svelte compiles code down to efficient JavaScript, it reduces the amount of framework code that needs to be shipped to the browser. This results in faster load times and improved performance, especially for users on slower networks. 

On the other hand, while being powerful, React applications often result in larger bundle sizes due to the inclusion of the React library and its associated tools. Although tree-shaking and code-splitting can mitigate this issue, the inherent size of the framework is still quite a challenge for performance optimization. 

Learning curve

We’ve already mentioned that, unlike more traditional frameworks, Svelte shifts much of its work to compile time, which means developers can write straightforward JavaScript, HTML, and CSS without needing to understand complex API or lifecycle methods. This can be especially appealing to beginners or those transitioning from vanilla JavaScript.

Moreover, Svelte’s syntax is intuitive and closely resembles standard HTML and JavaScript, which allows new developers to quickly grasp the concepts.

React, on the other hand, has a steeper learning curve. While it offers powerful features and flexibility, newcomers must familiarize themselves with concepts such as JSX, virtual DOM, state management, and component lifecycle methods. Not to mention hooks, which add another level of complexity.

Community and ecosystem

React has a vast and mature ecosystem, with 229k stars, 47k forks, and 1,666 contributors on GitHub. Its large community actively supports its growth and provides extensive documentation, tutorials, and third-party libraries, making it easy for developers to find resources and solutions.

While Svelte is gaining popularity among developers and boasts a high satisfaction rate, its community is still much smaller than React’s. However, given Svelte’s relatively young age, its growth is impressive. The official Svelte GitHub repository currently has 80k stars, 4.3k forks, and 738 contributors. Not to mention that in terms of ecosystem, thanks to its compiler functionality and small API surface, Svelte does not really need many additional tools. 

Still, React is the leader in this one.

Tooling and debugging

Svelte’s tooling is relatively straightforward. The framework comes with its own development environment, allowing developers to run and build projects with minimal setup. The Svelte DevTools extension for browsers is a great asset, providing insights into component structures and state management.

However, because Svelte is still newer compared to React, some developers may find fewer third-party tools and libraries specifically designed for Svelte. That said, the built-in debugging capabilities are often sufficient for many applications, and the simplicity of the code can sometimes make debugging more manageable.

React, on the other hand, shines in this aspect. The React Developer Tools extension is widely regarded as one of the best debugging tools available. It enables developers to inspect React component hierarchies in real-time, making it easier to track down issues in complex applications.

Moreover, React’s vast ecosystem offers a wealth of libraries and tools for state management (like Redux and MobX), routing (like React Router), and testing (like Jest and React Testing Library). This extensive support can help developers build robust applications but can overwhelm beginners with too many choices.

When to use React?

• Large-scale applications with complex state management: React’s component-based architecture and the availability of libraries like Redux or Context API make it ideal for large applications where data flows are complex and need to be managed across various parts of the UI.
• Projects requiring long-term support: React’s large community and mature ecosystem make it an excellent choice for applications that need long-term support and updates. The wealth of documentation, tools, and libraries ensures that React will remain relevant for years to come.
• Enterprise-grade applications: Enterprises often choose React because of its stability, scalability, and the availability of a wide range of developer tools and libraries. React’s ecosystem is battle-tested and trusted by many large organizations, like Meta, Airbnb and Netflix.

When to use Svelte?

• Small to medium-sized applications: Svelte is perfect for smaller applications where performance and quick development times are crucial. The reduced bundle size and direct DOM manipulation make it an excellent choice for apps that need to be lightweight and fast.
• Performance-critical applications: For projects where performance is a top priority — such as mobile apps or applications with bandwidth constraints — Svelte’s faster runtime performance and smaller bundle size offer significant advantages.
• Experimental or cutting-edge projects: If you’re working on an experimental project or one that requires cutting-edge technology, Svelte offers a fresh approach to building UIs, with its compilation model and built-in reactivity.

Svelte vs. React: what to choose?

Expert Opinion

All modern frontend solutions, such as React, Angular, Vue, and Svelte, are worth considering. However, if you’re deciding between React and Svelte, it can be helpful to evaluate key factors such as the size of the application, its lifecycle, and technical requirements.

Ultimately, both solutions are suitable for modern frontend projects and can deliver excellent results. Having a clear vision of the project’s business and technical details will help achieve better outcomes in the long term.

Frontend Developer at SoftTeco

Alexander Dikusar

Here is a head-to-head comparison table to help you evaluate the key differences between React and Svelte at a glance:

Final thoughts

As we compared Svelte vs. React, it’s clear that both tools are really powerful and incredibly useful. Choosing the right one will depend on striking the right balance between ecosystem support, performance, and development experience. React is a good choice for building large, complex applications with a mature ecosystem and extensive community support. 

On the other hand, Svelte offers a fresh, simpler approach to building UIs. With smaller bundle sizes, faster runtime performance, and less boilerplate code, Svelte is a great choice for small to medium-sized applications where performance and simplicity are key. Therefore, carefully consider all their pros and cons in the context of your project’s specific needs.