What is the Difference Between React and Solid.js?

If you are building modern web applications, you have likely used or heard of React. It has dominated the frontend landscape for years. However, Solid.js has emerged as a powerful challenger, offering a strikingly similar developer experience but with a completely different engine under the hood.

This guide breaks down the core differences, performance models, syntax comparisons, and setup processes for both frameworks.

The Core Difference: VDOM vs. Fine-Grained Reactivity

The fundamental difference between React and Solid.js lies in how they update the user interface when data changes.

React: The Virtual DOM (VDOM)

React uses a Virtual DOM. When a component’s state changes, React re-runs the entire component function and creates a new Virtual DOM tree. It then compares (diffs) this new tree with the old one and updates only the changed parts in the real browser DOM.

• The Catch: Re-running component functions can become expensive as your app grows, requiring optimization tools like useMemo and useCallback.

Solid.js: True Reactivity (No VDOM)

Solid.js completely eliminates the Virtual DOM. Instead, it compiles your code down to raw, surgical DOM updates. Component functions in Solid only run once when they are initialized. When state changes, only the specific DOM node bound to that piece of state updates directly.

• The Benefit: Incredible rendering speed and minimal memory overhead, rivaling vanilla JavaScript.

Syntax Comparison (Code Samples)

At first glance, Solid.js looks almost identical to React because both use JSX. However, notice how state management and component rendering behave differently.

1. Counter Component in React

import React, { useState, useEffect } from 'react';

export default function ReactCounter() {
  const [count, setCount] = useState(0);

useEffect(() => {
console.log(`React: Count is now ${count}`);
}, [count]);

return (
<div>
<p>Count: {count}</p>
<button onClick={() => setCount(count + 1)}>Increment</button>
</div>
);
}

2. Counter Component in Solid.js

import { createSignal, createEffect } from 'solid-js';

export default function SolidCounter() {
  // In Solid, useState is called createSignal
  const [count, setCount] = createSignal(0);

createEffect(() => {
// Solid automatically tracks dependencies; no dependency array needed!
console.log(`Solid: Count is now ${count()}`);
});

return (
<div>
{/* Notice that count is called as a function: count() */}
<p>Count: {count()}</p>
<button onClick={() => setCount(count() + 1)}>Increment</button>
</div>
);
}

Key Differences in the Code:

1. State Access: In React, count is a raw value. In Solid, count is a getter function, invoked as count(). This allows Solid to track exactly where the data is being used.
2. Effects: React’s useEffect requires an explicit dependency array [count]. Solid’s createEffect automatically detects which signals are called inside it and tracks them inherently.

Getting Started: Setup and Installation

Both frameworks are easiest to set up using Vite, a modern and ultra-fast build tool.

Setting Up React

To create a new React project with Vite, run the following commands in your terminal:

# Initialize Vite with React template
npm create vite@latest my-react-app -- --template react

# Navigate into the project

cd my-react-app

# Install dependencies and start the development server

npm install
npm run dev

Setting Up Solid.js

To create a new Solid.js project, you can use the official Vite template:

# Initialize Vite with Solid template
npm create vite@latest my-solid-app -- --template solid

# Navigate into the project
cd my-solid-app

# Install dependencies and start the development server
npm install
npm run dev

Quick Comparison Table

Which One Should You Choose?

Choose React if:

• You are looking for a job (React is still the most demanded skill in web development).
• You rely heavily on a massive ecosystem of third-party libraries (UI components, graphing utilities, etc.).
• You want a mature, well-tested framework with extensive stack overflow coverage.

Choose Solid.js if:

• Performance and bundle size are your absolute top priorities (e.g., low-end mobile devices).
• You love the JSX look of React but dislike the rules of hooks, dependency arrays, and stale closures.
• You want a modern framework that works closer to vanilla modern JavaScript.