In this article, I'll share the results of an experiment comparing four different methods for working with SVG icons in React projects. The goal was to determine which approach offers the best balance of output file size, build time, and development convenience.

Setup and Methodology

To conduct this comparison, I created four empty projects using Vite and installed the necessary modules for each method. For the icons, I utilized Material UI icons, which are ideal for projects without a need for custom designs, such as admin panels. When custom designs are required, designers usually create unique icon sets. The four methods I explored are:

• Pre-built Icon Libraries: Importing icons from the Material UI npm package.
• SVG as a Component: Using SVG files directly as components.
• SVG Sprite: Compiling icons into a single SVG sprite.
• SVG Paths: Storing the path data of SVG icons as constants.

Exclusion of Icon Fonts

Before diving into the comparison, it's important to note that using icons as fonts was not considered in this analysis. While this method was popular in the past, it has become outdated due to various limitations, such as lack of scalability and accessibility issues. Modern projects generally avoid this approach in favor of more flexible and accessible options.

Method 1: Using Pre-built Icon Libraries via npm

For the first method, I imported all the icons from the Material UI npm library and displayed them on the page in a loop. Each icon in the library is exported as a set of JavaScript files. This method is straightforward but doesn't allow for customization.

Method 2: SVG as a Component

In this approach, I used the SVGR plugin to import SVG files as React components. This method is useful when you have custom icons and need to use them as components within your application. However, it resulted in a longer build time due to the need to process a large number of icons.

Method 3: SVG Sprite

SVG sprites are an older but still relevant technique. I generated a sprite file containing all the icons and a JavaScript file with constants for referencing each icon. This method offers quick build times but requires an initial setup script for sprite generation.

Method 4: SVG Paths

The fourth method involves storing only the d attribute of the tag for each icon as a constant. This innovative approach reduces the file size significantly by omitting other SVG elements. However, handling transparency can be tricky, as semi-transparent elements are merged with the main path.

Comparison and Results

Bundle Size

Material UI npm Library: The main part of the bundle consists of minified code, leading to a relatively small size.
SVG as a Component: Slightly larger due to less effective minification.
SVG Sprite: Similar size to SVG components, with additional mapping to sprite IDs.
SVG Paths: The smallest bundle size, as only path data is stored.

Build Time

Material UI npm Library: Built in 20 seconds for 10,000 icons.
SVG as a Component: Slowest, taking a minute and a half for 14,000 icons.
SVG Sprite: Fast, with 14,000 icons built in 13 seconds.
SVG Paths: Fastest, with a significant reduction in build time compared to the other methods (14,000 in 6 seconds).

Development Convenience

Material UI npm Library: Least convenient, as icons are only identified by names.
SVG as a Component: Highly convenient, with the development environment displaying the SVG content.
SVG Sprite: Convenient, as a set of constants with JS documentation and icon images is generated.
SVG Paths: Potentially convenient with proper documentation generation, which could be automated with a script.

Conclusion

Each method has its pros and cons:

Material UI npm Library: Ideal for projects where the provided set of icons is sufficient, with minimal impact on build time.
SVG as a Component: Standard and convenient for React projects, albeit slower in build time.
SVG Sprite: Fast in build time but requires setup for sprite generation.
SVG Paths: Promising for its small bundle size and fast build time, with potential for further optimization.
For simplicity and standard usage, the SVGR plugin is recommended. However, if bundle size and build time are critical, the SVG Paths method is worth exploring further.

Thank you for reading! Let me know in the comments what you think of these methods and if there are other comparisons you'd like to see. If this post receives enough interest, I'll consider publishing the script used for generating SVG Paths.