Emotion vs styled-components: What are the differences?

Key Differences between Emotion and styled-components

1. Syntax: Emotion uses a JavaScript syntax, allowing styles to be written directly in JavaScript code using template literals. This enables dynamic styling by interpolating variables and logic within the styles. On the other hand, styled-components provides a CSS-in-JS approach where styles are defined using a special syntax that looks similar to CSS but is actually written in JavaScript.

2. Tagged Template Literal: In Emotion, styles are defined using a tagged template literal syntax, where styles are wrapped inside a function or component. This allows the styles to be composed and reused. styled-components also uses a similar concept of tagged template literals, but it provides more flexibility by allowing the use of nested styles and dynamic styling based on props.

3. CSS Prop: Emotion introduces a dedicated css prop, which allows styles to be applied on a per-component basis, making it easier to inline styles or apply styles conditionally. On the other hand, styled-components does not have a separate css prop, but instead uses the component style itself for applying styles.

4. Performance: Emotion is known for its superior performance compared to styled-components. It utilizes a technique called "atomic CSS" where styles are automatically extracted and deduplicated, resulting in smaller bundle sizes and faster rendering. Although styled-components has improved its performance over time, Emotion still holds an edge in terms of performance optimizations.

5. Server-side Rendering: Both Emotion and styled-components provide support for server-side rendering (SSR), but Emotion has better SSR performance out of the box. It can easily extract critical styles and hydrate them on the server-side, resulting in faster initial rendering. styled-components requires additional configuration and setup for SSR optimizations.

6. Community and Ecosystem: styled-components has a larger and more mature community compared to Emotion. As a result, it has a wider range of third-party libraries, plugins, and resources available. styled-components also has better tooling integration with popular IDEs like VSCode, which enhances the development experience. While Emotion also has a growing community, it may have a slightly smaller ecosystem in comparison.

In Summary, Emotion and styled-components differ in their syntax, tagged template literal usage, presence of a css prop, performance optimizations, server-side rendering capabilities, and the size and maturity of their respective communities and ecosystems.