SVG vs PNG: Which Format Should You Use?

SVG and PNG each have a place in modern web development. The wrong choice adds unnecessary bytes to your pages or degrades visual quality. Here’s how to decide quickly.

The fundamental difference

SVG is vector. It describes shapes mathematically — lines, curves, circles. Scale it to any size and it stays sharp. File size depends on the number and complexity of shapes, not the display resolution.

PNG is raster. It stores a grid of pixels. Scale it up and it blurs. File size depends on dimensions and color complexity. A 100×100 PNG is much smaller than a 1000×1000 PNG of the same image.

When to use SVG

Icons and UI elements

Icons are the canonical use case for SVG. A typical icon at 24×24px:

• SVG (optimized): 200–600 bytes
• PNG at 24×24: 800–2,000 bytes
• PNG at 48×48 (retina): 2,000–6,000 bytes
• PNG sprite (2x): 10,000–50,000 bytes

For icons, SVG wins on file size at every resolution, and it automatically looks sharp on any screen density (Retina, 4K, etc.) with no extra work.

Logos

Logos are typically geometric shapes — exactly what SVG excels at. A logo in SVG is small, renders crisply at any size, and can be colored with CSS. If your logo is mostly shapes and text, SVG is the right choice.

Illustrations and charts

Geometric illustrations, diagrams, and charts (especially those generated by JavaScript libraries like D3) are natural SVG candidates. They scale with the viewport and can be interactive.

Animations

SVG elements can be animated with CSS transitions, CSS animations, or the Web Animations API. Animating a PNG requires canvas or image swapping. For animated UI elements, SVG is almost always the better choice.

When to use PNG

Photographs

A photograph converted to SVG would be enormous — every pixel becomes a colored rectangle. Photographs belong in JPEG or WebP, and PNG when transparency is needed.

Highly detailed illustrations with textures

Illustrations with photographic textures, complex gradients, or millions of small details (pixel art, detailed maps) are better as raster images. SVG can technically represent these, but the file size explodes.

Screenshots and UI mockups

Screenshots are inherently raster. Use PNG or WebP.

File size comparison: real numbers

The illustration row shows where PNG wins: a detailed raster image is smaller as PNG than as SVG. Beyond roughly 50 unique shapes, the cross-over point depends heavily on the image.

Browser support

SVG has full browser support across all modern browsers. You don’t need PNG fallbacks for SVG in 2025 — IE11 is gone.

Accessibility

SVG supports semantic markup. You can add role="img", aria-label, and <title> elements directly inside the SVG. PNG requires the surrounding <img> tag’s alt attribute.

Quick decision guide

• Icon, logo, geometric illustration → SVG
• Photo, screenshot, textured illustration → PNG / WebP
• Needs animation → SVG
• Needs CSS color theming → SVG
• Needs transparency → either works (SVG natively, PNG with alpha)

Once you’ve chosen SVG, make sure you optimize it before deploying. See how to optimize SVG files for the full workflow, and SVG and web performance for the impact on Core Web Vitals.