SVG Optimization: Less Weight, Less DOM, Faster Rendering
Practical SVG optimization: cleaning with SVGO, simplifying paths, reusing symbol and use, and reducing DOM size.
Joan León explains how to optimize SVG properly in practice, from basic file cleanup to optimizing repeated icons. The article is good because it shows both the tools and exactly where performance is lost.
Here are a few useful insights 👇
⚙️ Start by cleaning up the SVG
Exports from Figma/Illustrator almost always contain junk: metadata, comments, unnecessary g elements, inline styles, and so on.
Tools like SVGO remove this automatically and often shrink the file by 30–70%.
🧹 Simplify paths
Design tools generate overly complex path elements.
Sometimes the same shape can be described much more simply, reducing SVG size and speeding up parsing.
📦 Use SVG symbols for repeated icons
If the same icon appears on a page dozens of times, the browser creates a separate DOM for each instance.
It’s better to move it into a <symbol> and reuse it through <use>:
<svg>
<use href="#icon-check"></use>
</svg>This significantly reduces the DOM and saves memory.
🎨 Remove inline styles
Many SVGs arrive with lots of style="fill:#000" attributes and similar declarations.
Usually, it’s better to move these into CSS: the file becomes smaller, and the icons are easier to reuse.
🚫 Don’t overuse SVG
Sometimes a regular img or even a CSS shape will be simpler and faster. SVG is good for icons, illustrations, and vector graphics, but it isn’t always the best choice.
💡 The article’s main point:
SVG is often considered a “free” format, but large numbers of icons can noticeably inflate the DOM and affect performance.