Why don’t SVG images scale using the CSS “width” property?

To the roots: Understanding viewbox

Let's dissect the SVG's viewBox. Imagine it as a stage with min-x and min-y as the left bottom corner and width and height as stage sizes. The scaling act of SVG content unfolds here:

<svg viewBox="min-x min-y width height">
  <!-- SVG theatrics -->
</svg>
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Fixed dimensions: A double-edged sword

When dealing with SVGs, a consistent offender is hardcoded width and height. Free your SVG from these shackles and let CSS take the wheel:

<!-- Behold, a roadblock -->
<svg width="100" height="100" viewBox="0 0 100 100">
  <!-- SVG artwork -->
</svg>

<!-- Make way for CSS! -->
<svg viewBox="0 0 100 100">
  <!-- SVG artwork -->
</svg>


CSS Transforms: Beyond basic scaling

Heighten your scaling prowess with CSS transform: scale(value). It inflates or shrinks elements while maintaining their aspect ratio.

svg {
  transform: scale(2); /* Double bubble trouble, it's 2x time! */
}
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Diving deeper: Advanced consideration for SVG scaling

You've got the basics down, now it's time for scene two - the advanced tips.

Scene with Flexbox: Expect the unexpected

When dealing with Flexbox, ensure your SVG can adapt to plot twists. SVG size can vary as Flexbox controls the spacing and alignment, so keep your SVG ready for any scene:

.container {
  display: flex;
}
.container svg {
  flex: 1; /* The SVG is now a method actor and adjusts to the role */
}


Read the script: Edit SVG attributes

Occasionally, the viewBox isn't well-defined or needs changes. Here, editing the SVG viewBox by opening the script (SVG file) in a text editor, and changing the viewBox directly works like a charm:

Casting right: Align viewbox with CSS

Casting the right actor for the right part is crucial. Align your viewBox values with CSS dimensions to ensure your SVG delivers a consistent performance across different screen sizes and environments.