React vs solid.js: Key Differences and When to Use Each

React is a popular UI library using a virtual DOM and declarative components with hooks, while solid.js offers fine-grained reactivity with no virtual DOM for faster updates and simpler reactivity. Both build user interfaces but differ in performance and reactivity models.

Quick Comparison

Here is a quick side-by-side look at React and solid.js on key factors.

Factor	React	solid.js
Reactivity Model	Virtual DOM with diffing	Fine-grained reactive primitives
Performance	Good, but virtual DOM overhead	Very fast, no virtual DOM
Component Type	Functional components with hooks	Functions with reactive signals
Learning Curve	Moderate, popular ecosystem	Slightly steeper due to reactivity model
Bundle Size	Larger (~40-50KB gzipped)	Smaller (~10KB gzipped)
Community & Ecosystem	Very large and mature	Smaller but growing

Key Differences

React uses a virtual DOM to track changes and update the UI efficiently by comparing old and new virtual trees. This approach simplifies UI updates but adds some overhead during diffing and rendering. React components are built with hooks like useState and useEffect to manage state and side effects declaratively.

solid.js skips the virtual DOM entirely. Instead, it uses fine-grained reactivity with signals and computations that update only the parts of the UI that depend on changed data. This leads to faster updates and less memory use. Its components are simple functions that create reactive dependencies automatically.

React’s ecosystem is vast with many tools and libraries, making it easier for beginners to find resources. solid.js is newer and smaller but offers better runtime performance and smaller bundle sizes, which is great for performance-critical apps.

Code Comparison

Here is a simple counter example in React using functional components and hooks.

javascript

import React, { useState } from 'react';

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

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

Output

A button labeled 'Increment' and a text 'Count: 0' that updates to 'Count: 1', 'Count: 2', etc. when clicked.

solid.js Equivalent

The same counter implemented in solid.js uses signals for reactivity.

javascript

import { createSignal } from 'solid-js';

export default function Counter() {
  const [count, setCount] = createSignal(0);

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

Output

A button labeled 'Increment' and a text 'Count: 0' that updates to 'Count: 1', 'Count: 2', etc. when clicked.

When to Use Which

Choose React when you want a mature, widely supported library with a huge ecosystem, many tutorials, and third-party tools. It’s great for large teams and projects where community support and stability matter.

Choose solid.js when performance is critical and you want minimal runtime overhead with fine-grained reactivity. It’s ideal for apps needing fast updates and smaller bundles, or when you want to explore a modern reactive approach without a virtual DOM.

Key Takeaways

React uses a virtual DOM and hooks for declarative UI updates with a large ecosystem.

solid.js uses fine-grained reactivity without a virtual DOM for faster, smaller apps.

React is better for broad community support and mature tooling.

solid.js excels in performance and minimal runtime overhead.

Choose based on your project needs: ecosystem vs performance.