SVG, PNG and ICO solve different problems. Choosing only by file size can produce poor results because a lightweight format may still be unsuitable for the place where it is displayed.

Consider scaling, transparency, compatibility, animation and the way the asset will be integrated into the project.

Use SVG for interfaces and scalable libraries

SVG describes shapes as vectors, so the same file stays sharp at 16 or 512 pixels. It is ideal for interface icons, simple logos and libraries that need CSS-driven colors.

It also supports accessibility and animation. Photographs or extremely detailed artwork, however, are not good candidates for automatic vector conversion.

  • Scales without pixelation.
  • Can be styled or animated with CSS.
  • Works well in reusable components.
  • Must be sanitized when sourced from untrusted input.

Use PNG to preserve pixels and transparency

PNG is a lossless raster format suited to transparent artwork, screenshots and graphics that must retain exact pixel data. It works consistently across browsers and editors.

Its limitation is fixed resolution. A 32-pixel PNG becomes blurry when enlarged, so provide enough source resolution for high-density screens.

Use ICO mainly for favicons

ICO can hold several resolutions in one container. The browser chooses the most appropriate frame for tabs, bookmarks or shortcuts, which makes it especially useful for favicons.

It is not a good default for in-page interface assets, where SVG or PNG gives better control.

Combine formats instead of forcing one choice

Most web projects use SVG for interface icons, PNG for raster images and ICO for the favicon. Multiple formats can represent the same visual identity as long as they are generated from a consistent source.

public/
├── favicon.ico
├── favicon-16x16.png
├── favicon-32x32.png
└── icons/
    ├── search.svg
    ├── user.svg
    └── logo.png

Choose based on the real use case

Ask whether the icon must change color, scale, support old browsers, represent a photograph or serve as a favicon. These answers are more reliable than a universal rule.

  • Interface and design system: SVG.
  • Raster image with transparency: PNG.
  • Multi-size favicon: ICO plus PNG.
  • Rich social preview: PNG or JPEG, depending on the artwork.

Frequently asked questions